SVM129-BOCTOBER, 2006
Safety Depends on You
Lincoln arc welding and cuttingequipment is designed and builtwith safety in mind. However,your overall safety can beincreased by proper installation .. . and thoughtful operation onyour part. DO NOT INSTALL,OPERATE OR REPAIR THISEQUIPMENT WITHOUT READ-ING THIS MANUAL AND THESAFETY PRECAUTIONS CON-TAINED THROUGHOUT. And,most importantly, think beforeyou act and be careful.
For use with machine code numbers:10151,10152,10153,10309,10381,10382,10383,11090,11091,11092,
11115,11116
INVERTEC ® STT TM & STT II TM
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SERVICE MANUAL
• Sales and Service through Subsidiaries and Distributors Worldwide •
Cleveland, Ohio 44117-1199 U.S.A. TEL: 1-888-935-3877 FAX: 216.486.1751 WEB SITE: www.lincolnelectric.com
• World's Leader in Welding and Cutting Products •
Copyright © 2006 Lincoln Global Inc.
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FOR ENGINEpowered equipment.
1.a. Turn the engine off before troubleshooting and maintenancework unless the maintenance work requires it to be running.
____________________________________________________1.b. Operate engines in open, well-ventilated
areas or vent the engine exhaust fumes outdoors.
____________________________________________________1.c. Do not add the fuel near an open flame weld-
ing arc or when the engine is running. Stopthe engine and allow it to cool before refuel-ing to prevent spilled fuel from vaporizing oncontact with hot engine parts and igniting. Donot spill fuel when filling tank. If fuel is spilled,wipe it up and do not start engine until fumeshave been eliminated.
____________________________________________________1.d. Keep all equipment safety guards, covers and devices in posi-
tion and in good repair.Keep hands, hair, clothing and toolsaway from V-belts, gears, fans and all other moving partswhen starting, operating or repairing equipment.
____________________________________________________
1.e. In some cases it may be necessary to remove safetyguards to perform required maintenance. Removeguards only when necessary and replace them when themaintenance requiring their removal is complete.Always use the greatest care when working near movingparts.
___________________________________________________1.f. Do not put your hands near the engine fan.
Do not attempt to override the governor oridler by pushing on the throttle control rodswhile the engine is running.
___________________________________________________1.g. To prevent accidentally starting gasoline engines while
turning the engine or welding generator during maintenancework, disconnect the spark plug wires, distributor cap ormagneto wire as appropriate.
iSAFETYi
ARC WELDING CAN BE HAZARDOUS. PROTECT YOURSELF AND OTHERS FROM POSSIBLE SERIOUS INJURY OR DEATH.KEEP CHILDREN AWAY. PACEMAKER WEARERS SHOULD CONSULT WITH THEIR DOCTOR BEFORE OPERATING.
Read and understand the following safety highlights. For additional safety information, it is strongly recommended that youpurchase a copy of “Safety in Welding & Cutting - ANSI Standard Z49.1” from the American Welding Society, P.O. Box 351040,Miami, Florida 33135 or CSA Standard W117.2-1974. A Free copy of “Arc Welding Safety” booklet E205 is available from theLincoln Electric Company, 22801 St. Clair Avenue, Cleveland, Ohio 44117-1199.
BE SURE THAT ALL INSTALLATION, OPERATION, MAINTENANCE AND REPAIR PROCEDURES AREPERFORMED ONLY BY QUALIFIED INDIVIDUALS.
WARNING
Mar ‘95
ELECTRIC AND MAGNETIC FIELDSmay be dangerous
2.a. Electric current flowing through any conductor causes localized Electric and Magnetic Fields (EMF). Welding current creates EMF fields around welding cables and welding machines
2.b. EMF fields may interfere with some pacemakers, andwelders having a pacemaker should consult their physicianbefore welding.
2.c. Exposure to EMF fields in welding may have other healtheffects which are now not known.
2.d. All welders should use the following procedures in order tominimize exposure to EMF fields from the welding circuit:
2.d.1. Route the electrode and work cables together - Securethem with tape when possible.
2.d.2. Never coil the electrode lead around your body.
2.d.3. Do not place your body between the electrode andwork cables. If the electrode cable is on your right side, the work cable should also be on your right side.
2.d.4. Connect the work cable to the workpiece as close aspossible to the area being welded.
2.d.5. Do not work next to welding power source.
1.h. To avoid scalding, do not remove theradiator pressure cap when the engine ishot.
CALIFORNIA PROPOSITION 65 WARNINGS
Diesel engine exhaust and some of its constituentsare known to the State of California to cause can-cer, birth defects, and other reproductive harm.
The engine exhaust from this product containschemicals known to the State of California to causecancer, birth defects, or other reproductive harm.
The Above For Diesel Engines The Above For Gasoline Engines
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4.a. Use a shield with the proper filter and coverplates to protect your eyes from sparks andthe rays of the arc when welding or observingopen arc welding. Headshield and filter lensshould conform to ANSI Z87. I standards.
4.b. Use suitable clothing made from durable flame-resistantmaterial to protect your skin and that of your helpers fromthe arc rays.
4.c. Protect other nearby personnel with suitable, non-flammablescreening and/or warn them not to watch the arc nor exposethemselves to the arc rays or to hot spatter or metal.
ELECTRIC SHOCK can kill.3.a. The electrode and work (or ground) circuits
are electrically “hot” when the welder is on.Do not touch these “hot” parts with your bareskin or wet clothing. Wear dry, hole-freegloves to insulate hands.
3.b. Insulate yourself from work and ground using dry insulation.Make certain the insulation is large enough to cover your fullarea of physical contact with work and ground.
In addition to the normal safety precautions, if weldingmust be performed under electrically hazardousconditions (in damp locations or while wearing wetclothing; on metal structures such as floors, gratings orscaffolds; when in cramped positions such as sitting,kneeling or lying, if there is a high risk of unavoidable oraccidental contact with the workpiece or ground) usethe following equipment:
• Semiautomatic DC Constant Voltage (Wire) Welder.• DC Manual (Stick) Welder.• AC Welder with Reduced Voltage Control.
3.c. In semiautomatic or automatic wire welding, the electrode,electrode reel, welding head, nozzle or semiautomaticwelding gun are also electrically “hot”.
3.d. Always be sure the work cable makes a good electricalconnection with the metal being welded. The connectionshould be as close as possible to the area being welded.
3.e. Ground the work or metal to be welded to a good electrical(earth) ground.
3.f. Maintain the electrode holder, work clamp, welding cable andwelding machine in good, safe operating condition. Replacedamaged insulation.
3.g. Never dip the electrode in water for cooling.
3.h. Never simultaneously touch electrically “hot” parts ofelectrode holders connected to two welders because voltagebetween the two can be the total of the open circuit voltageof both welders.
3.i. When working above floor level, use a safety belt to protectyourself from a fall should you get a shock.
3.j. Also see Items 6.c. and 8.
FUMES AND GASEScan be dangerous.5.a. Welding may produce fumes and gases
hazardous to health. Avoid breathing thesefumes and gases.When welding, keepyour head out of the fume. Use enoughventilation and/or exhaust at the arc to keep
fumes and gases away from the breathing zone. Whenwelding with electrodes which require specialventilation such as stainless or hard facing (seeinstructions on container or MSDS) or on lead orcadmium plated steel and other metals or coatingswhich produce highly toxic fumes, keep exposure aslow as possible and below Threshold Limit Values (TLV)using local exhaust or mechanical ventilation. Inconfined spaces or in some circumstances, outdoors, arespirator may be required. Additional precautions arealso required when welding on galvanized steel.
5. b. The operation of welding fume control equipment is affectedby various factors including proper use and positioning of theequipment, maintenance of the equipment and the specificwelding procedure and application involved. Worker expo-sure level should be checked upon installation and periodi-cally thereafter to be certain it is within applicable OSHA PELand ACGIH TLV limits.
5.c. Do not weld in locations near chlorinated hydrocarbon vaporscoming from degreasing, cleaning or spraying operations.The heat and rays of the arc can react with solvent vapors toform phosgene, a highly toxic gas, and other irritating prod-ucts.
5.d. Shielding gases used for arc welding can displace air andcause injury or death. Always use enough ventilation,especially in confined areas, to insure breathing air is safe.
5.e. Read and understand the manufacturer’s instructions for thisequipment and the consumables to be used, including thematerial safety data sheet (MSDS) and follow youremployer’s safety practices. MSDS forms are available fromyour welding distributor or from the manufacturer.
5.f. Also see item 1.b.
AUG 06
iiSAFETYii
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FOR ELECTRICALLYpowered equipment.
8.a. Turn off input power using the disconnectswitch at the fuse box before working onthe equipment.
8.b. Install equipment in accordance with the U.S. NationalElectrical Code, all local codes and the manufacturer’srecommendations.
8.c. Ground the equipment in accordance with the U.S. NationalElectrical Code and the manufacturer’s recommendations.
CYLINDER may explodeif damaged.7.a. Use only compressed gas cylinders
containing the correct shielding gas for theprocess used and properly operatingregulators designed for the gas and
pressure used. All hoses, fittings, etc. should be suitable forthe application and maintained in good condition.
7.b. Always keep cylinders in an upright position securelychained to an undercarriage or fixed support.
7.c. Cylinders should be located:• Away from areas where they may be struck or subjected tophysical damage.
• A safe distance from arc welding or cutting operations andany other source of heat, sparks, or flame.
7.d. Never allow the electrode, electrode holder or any otherelectrically “hot” parts to touch a cylinder.
7.e. Keep your head and face away from the cylinder valve outletwhen opening the cylinder valve.
7.f. Valve protection caps should always be in place and handtight except when the cylinder is in use or connected foruse.
7.g. Read and follow the instructions on compressed gascylinders, associated equipment, and CGA publication P-l,“Precautions for Safe Handling of Compressed Gases inCylinders,” available from the Compressed Gas Association1235 Jefferson Davis Highway, Arlington, VA 22202.
Mar ‘95
WELDING SPARKS cancause fire or explosion.6.a. Remove fire hazards from the welding area.
If this is not possible, cover them to preventthe welding sparks from starting a fire.Remember that welding sparks and hot
materials from welding can easily go through small cracksand openings to adjacent areas. Avoid welding nearhydraulic lines. Have a fire extinguisher readily available.
6.b. Where compressed gases are to be used at the job site,special precautions should be used to prevent hazardoussituations. Refer to “Safety in Welding and Cutting” (ANSIStandard Z49.1) and the operating information for theequipment being used.
6.c. When not welding, make certain no part of the electrodecircuit is touching the work or ground. Accidental contact cancause overheating and create a fire hazard.
6.d. Do not heat, cut or weld tanks, drums or containers until theproper steps have been taken to insure that such procedureswill not cause flammable or toxic vapors from substancesinside. They can cause an explosion even though they havebeen “cleaned”. For information, purchase “RecommendedSafe Practices for the Preparation for Welding and Cutting ofContainers and Piping That Have Held HazardousSubstances”, AWS F4.1 from the American Welding Society(see address above).
6.e. Vent hollow castings or containers before heating, cutting orwelding. They may explode.
6.f. Sparks and spatter are thrown from the welding arc. Wear oilfree protective garments such as leather gloves, heavy shirt,cuffless trousers, high shoes and a cap over your hair. Wearear plugs when welding out of position or in confined places.Always wear safety glasses with side shields when in awelding area.
6.g. Connect the work cable to the work as close to the weldingarea as practical. Work cables connected to the buildingframework or other locations away from the welding areaincrease the possibility of the welding current passingthrough lifting chains, crane cables or other alternate circuits.This can create fire hazards or overheat lifting chains orcables until they fail.
6.h. Also see item 1.c.
iiiSAFETYiii
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OC PRÉCAUTIONS DE SÛRETÉ
Pour votre propre protection lire et observer toutes les instructionset les précautions de sûreté specifiques qui parraissent dans cemanuel aussi bien que les précautions de sûreté générales suiv-antes:
Sûreté Pour Soudage A L’Arc1. Protegez-vous contre la secousse électrique:
a. Les circuits à l’électrode et à la piéce sont sous tensionquand la machine à souder est en marche. Eviter toujourstout contact entre les parties sous tension et la peau nueou les vétements mouillés. Porter des gants secs et sanstrous pour isoler les mains.
b. Faire trés attention de bien s’isoler de la masse quand onsoude dans des endroits humides, ou sur un plancher met-allique ou des grilles metalliques, principalement dans les positions assis ou couché pour lesquelles une grandepartie du corps peut être en contact avec la masse.
c. Maintenir le porte-électrode, la pince de masse, le câble desoudage et la machine à souder en bon et sûr état defonc-tionnement.
d.Ne jamais plonger le porte-électrode dans l’eau pour lerefroidir.
e. Ne jamais toucher simultanément les parties sous tensiondes porte-électrodes connectés à deux machines à souderparce que la tension entre les deux pinces peut être le totalde la tension à vide des deux machines.
f. Si on utilise la machine à souder comme une source decourant pour soudage semi-automatique, ces precautionspour le porte-électrode s’applicuent aussi au pistolet desoudage.
2. Dans le cas de travail au dessus du niveau du sol, se protégercontre les chutes dans le cas ou on recoit un choc. Ne jamaisenrouler le câble-électrode autour de n’importe quelle partie ducorps.
3. Un coup d’arc peut être plus sévère qu’un coup de soliel, donc:
a. Utiliser un bon masque avec un verre filtrant approprié ainsiqu’un verre blanc afin de se protéger les yeux du rayon-nement de l’arc et des projections quand on soude ouquand on regarde l’arc.
b. Porter des vêtements convenables afin de protéger la peaude soudeur et des aides contre le rayonnement de l‘arc.
c. Protéger l’autre personnel travaillant à proximité ausoudage à l’aide d’écrans appropriés et non-inflammables.
4. Des gouttes de laitier en fusion sont émises de l’arc desoudage. Se protéger avec des vêtements de protection libresde l’huile, tels que les gants en cuir, chemise épaisse, pan-talons sans revers, et chaussures montantes.
5. Toujours porter des lunettes de sécurité dans la zone desoudage. Utiliser des lunettes avec écrans lateraux dans les
zones où l’on pique le laitier.
6. Eloigner les matériaux inflammables ou les recouvrir afin deprévenir tout risque d’incendie dû aux étincelles.
7. Quand on ne soude pas, poser la pince à une endroit isolé dela masse. Un court-circuit accidental peut provoquer unéchauffement et un risque d’incendie.
8. S’assurer que la masse est connectée le plus prés possible dela zone de travail qu’il est pratique de le faire. Si on place lamasse sur la charpente de la construction ou d’autres endroitséloignés de la zone de travail, on augmente le risque de voirpasser le courant de soudage par les chaines de levage,câbles de grue, ou autres circuits. Cela peut provoquer desrisques d’incendie ou d’echauffement des chaines et descâbles jusqu’à ce qu’ils se rompent.
9. Assurer une ventilation suffisante dans la zone de soudage.Ceci est particuliérement important pour le soudage de tôlesgalvanisées plombées, ou cadmiées ou tout autre métal quiproduit des fumeés toxiques.
10. Ne pas souder en présence de vapeurs de chlore provenantd’opérations de dégraissage, nettoyage ou pistolage. Lachaleur ou les rayons de l’arc peuvent réagir avec les vapeursdu solvant pour produire du phosgéne (gas fortement toxique)ou autres produits irritants.
11. Pour obtenir de plus amples renseignements sur la sûreté, voirle code “Code for safety in welding and cutting” CSA StandardW 117.2-1974.
PRÉCAUTIONS DE SÛRETÉ POURLES MACHINES À SOUDER ÀTRANSFORMATEUR ET ÀREDRESSEUR
1. Relier à la terre le chassis du poste conformement au code del’électricité et aux recommendations du fabricant. Le dispositifde montage ou la piece à souder doit être branché à unebonne mise à la terre.
2. Autant que possible, I’installation et l’entretien du poste seronteffectués par un électricien qualifié.
3. Avant de faires des travaux à l’interieur de poste, la debranch-er à l’interrupteur à la boite de fusibles.
4. Garder tous les couvercles et dispositifs de sûreté à leur place.
Mar. ‘93
ivSAFETYiv
MASTER TABLE OF CONTENTS FOR ALL SECTIONSv v
INVERTEC STT
PageSafety .................................................................................................................................................i-iv
Installation .............................................................................................................................Section A
Operation...............................................................................................................................Section B
Accessories ..........................................................................................................................Section C
Maintenance ..........................................................................................................................Section D
Theory of Operation .............................................................................................................Section E
Troubleshooting and Repair ................................................................................................Section F
Electrical Diagrams ..............................................................................................................Section G
STT Parts .......................................................................................................................................P257STT II Parts ....................................................................................................................................P294
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TABLE OF CONTENTS- INSTALLATION SECTION -
Section A-1 Section A-1
INVERTEC STT
Installation .............................................................................................................................Section A
Technical Specifications (Codes 11092 & Below).......................................................................A-2
Technical Specifications (Codes 11115 & 11116) ........................................................................A-3
Location.......................................................................................................................................A-4
Stacking.......................................................................................................................................A-4
Tilting...........................................................................................................................................A-4
Machine Grounding and High Frequency Interference Protection..............................................A-4
Input Connections .......................................................................................................................A-4
Supply Connections..............................................................................................................A-4
Input Cable Installation and Connection...............................................................................A-5
Ground Connection...............................................................................................................A-5
Input Voltage Reconnect Procedure ...........................................................................................A-6
Output Connections ....................................................................................................................A-6
Wire Feeder Output Connections .........................................................................................A-6
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INSTALLATIONA-2 A-2
INVERTEC STT
STANDARD VOLTAGE INPUT CURRENT AT RATED OUTPUT
208/230/460/3/60 HZ 32/30/16
200/220/380/415/440/3/50/60 HZ 33/30/18/17/16
TECHNICAL SPECIFICATIONS –Invertec STT & STT II (For Codes 11092 and BELOW)INPUT- THREE PHASE ONLY
RATED OUTPUT
RECOMMENDED INPUT WIRE AND FUSE SIZESINPUT VOLTAGE FUSE(SUPER LAG) INPUT AMPERE TYPE 75 C TYPE 75 C
AND FREQUENCY OR BREAKER RATING ON COPPER COPPERSIZE NAMEPLATE SUPPLY WIRE GROUND WIRE
IN CONDUIT IN CONDUITAWG (IEC) SIZES AWG (IEC) SIZES
208/60 40 32230/60 40 30460/60 30 16200/50/60 40 33
220/50/60 40 30 10 (6 mm2) 10 (6 mm2)380/50/60 30 18415/50/60 30 17440/50/60 30 16
HEIGHT WIDTH DEPTH WEIGHT
23.2 in 13.2 in. 24.4 in. 100 lbs.
589 mm 336 mm 620 mm 46 kg
OUTPUT
DUTY CYCLE AMPS VOLTS AT RATED AMPS
60% Duty Cycle 225 29
100% Duty Cycle 200 28
CURRENT RANGE OPEN CIRCUIT VOLTAGE AUXILIARY POWER
Peak Current 1 0 - 450 Amps 85 VDC Maximum 115 2 VAC @ 4 AmpsBackground 0 - 125 Amps 42 VAC @ 4 Amps
1 At low input voltages (below 208 VAC) and input voltages of 380 VAC through 415 VAC there may be a 15% reduction in Peak Current.
2 115 VAC not present on European Models.
PHYSICAL DIMENSIONS
INSTALLATIONA-3 A-3
INVERTEC STTRet
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STANDARD VOLTAGE INPUT CURRENT AT RATED OUTPUT
200/208/3/50/60 HZ 36/34
200/208/380/400/415/3/50/60 HZ 36/34/20/19/18
TECHNICAL SPECIFICATIONS –Invertec STT II (For Codes 11115 AND 11116)INPUT- THREE PHASE ONLY
RATED OUTPUT
RECOMMENDED INPUT WIRE AND FUSE SIZESINPUT VOLTAGE FUSE(SUPER LAG) INPUT AMPERE TYPE 75 C TYPE 75 C
AND FREQUENCY OR BREAKER RATING ON COPPER COPPERSIZE NAMEPLATE SUPPLY WIRE GROUND WIRE
IN CONDUIT IN CONDUITAWG (IEC) SIZES AWG (IEC) SIZES
200/50/60 40 36208/50/60 40 34
380/50/60 30 20 10 (6 mm2) 10 (6 mm2)400/50/60 30 19415/50/60 30 18
HEIGHT WIDTH DEPTH WEIGHT
23.2 in 13.2 in. 24.4 in. 100 lbs.
589 mm 336 mm 620 mm 46 kg
OUTPUT
DUTY CYCLE AMPS VOLTS AT RATED AMPS
60% Duty Cycle 225 29
100% Duty Cycle 200 28
CURRENT RANGE OPEN CIRCUIT VOLTAGE AUXILIARY POWER
Peak Current 0 - 450 Amps 88 VDC Maximum 115 1 VAC @ 4 AmpsBackground 0 - 125 Amps 42 VAC @ 4 Amps
1 115 VAC not present on European Models.
PHYSICAL DIMENSIONS
INSTALLATIONA-4 A-4
INVERTEC STTRet
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ELECTRIC SHOCK can kill.• Only qualified personnel should
perform this installation.
• Turn the input power OFF at the disconnect switch or fuse box before installing this equipment.
• Turn the power switch on the Invertec STT “OFF” before connecting or discon-necting input power lines, output cables, or control cables.
• Do not touch electrically hot parts.
• Always connect the ground terminal to agood electrical earth ground.
WARNING
MACHINE GROUNDING AND HIGHFREQUENCY INTERFERENCE PROTECTION
The machine may not be suitable for use in an envi-ronment where high frequency is present. For exam-ple do not place the machine in close proximity to “TIG”or “PLASMA” operations. To minimize high frequencyinterference:
Locate the STT II power source more than 15feet (4.5 m) away from high frequency unitsand more than 25 feet (7.6 m) separationbetween ground connections or welding arcsof high frequency units.
Provide proper electrical ground to themachine per local and national electricalcodes.
INPUT CONNECTIONS
FAILURE TO FOLLOW THESE INSTRUCTIONSCAN CAUSE IMMEDIATE FAILURE OF COMPO-NENTS WITHIN THE WELDER.
Turn the input power off at the disconnect switchbefore attempting to connect the input power lines.
Connect the green lead of the power cord to groundper local and national electrical codes.
SUPPLY CONNECTIONS
Be sure the voltage, phase, and frequency of the inputsupply is as specified on the rating plate. Input Powersupply line entry in provided on the case back of themachine. See figure A.1 for location of the rating plate.
The Invertec STT II should be connected only by aqualified electrician. Installation should be made inaccordance with local and national codes. Refer to the“Technical Specifications” at the beginning of thissection for proper fuse sizes, ground wire, and inputsupply power cable sizes.
Some models come from the factory with an inputpower cord. If your model does not include the inputpower cord install the proper size input cable andground cable according to “INPUT CABLE INSTAL-LATION AND CONNECTION”.
SELECT SUITABLE LOCATION
Locate the machine where there is free circulation ofclean air. Place the machine so that air can freely cir-culate into the sides and out of the rear of themachine. Dirt and dust that can be drawn into themachine should be kept to a minimum. Failure toobserve these precautions can result in excessiveoperating temperatures and nuisance shut down of theInvertec STT II.
This machine carries an enclosure rating of IP21S. Itshould not be placed in extremely damp or dirty loca-tions. It should not be exposed to rain or snow.
STACKING
The Invertec STT II cannot be stacked.
TILTING
Place the machine on a secure, level surface otherwisethe unit may topple over.
Read and understand entire InstallationSection before starting installation.
INSTALLATIONA-5 A-5
INVERTEC STTRet
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INPUT CABLE INSTALLATION AND CON-NECTION
A cable strain relief is provided at the supply line entryand is designed to accommodate cable diameters of.310 - 1.070 in. (7.9 - 27.2 mm). On European modelsthe strain relief is designed to accommodate cablediameters of .709 - 1.000 in. (18.0 - 25.4 mm). Refer to“Technical Specifications” at the beginning of this sec-tion for the proper input cable sizes. Refer to Figure A.1and perform the following steps:
1. Remove the wraparound cover of the Invertec STT II.
2. Feed the input cable through the input cableentry access hole at the right rear of themachine.
3. Route the cable through the cable hangers, located along the lower right inside edge of the machine, up to the power switch located onthe front panel.
4. Strip away 102 mm (4 in.) of the outer jacket. Trim fillers and strip conductor jackets to connect to the power switch.
5. Connect the three phase line con-ductors to the power switch termi-nals labeled U, V and W. Tightenthe connections to 3.0 Nm. (27 in.-lb.) torque.
6. Securely tighten the cable strain relief locatedon the case back of the machine.
GROUND CONNECTION
1. Connect the ground terminal to earth ground per National Electrical Code.
2. Replace the wraparound cover of the Invertec STT II.
CASE BACK
RATING PLATEINPUT CABLEENTRY ACCESS& CABLE STRAIN RELIEF
FIGURE A.1 CASE BACK
A-6INSTALLATION A-6
INVERTEC STT II
FIGURE A.2 RECONNECT PANELINPUT VOLTAGE RECONNECTPROCEDURE
As shipped from the factory, multiple voltage machinesare internally configured for the highest input voltage(440-460 VAC), for Codes 11092 and below and (380-415 VAC), for Codes 11115 and 11116.
1. For Connections to 440 or 460 VAC verify the inter-nal configurations to the procedures shown below andrefer to Figure A.2.
2. For Connections to 200,208,220,230,380,400 or 415VAC follow the procedure shown below and refer to fig-ure A.2.
NOTE: Turn main power to the machine OFF
before performing the reconnect procedure.Failure to do so will result in damage to themachine. DO NOT switch the reconnect bar withmachine power ON.------------------------------------------------------------------------
To Operate at Procedure
460 or 440 VAC 1. Open reconnect panel (Codes 11092 and access door on wrap-around.below) 2. Move input voltage switch
to Voltage = 380 -460V pos-ition.
3. Move lead “A” to 440-460 Terminal.
380 or 415 VAC 1. Open reconnect panel(Codes 11092 and access door on wrap-around.below)
2. Move input voltage switch to Voltage = 380-460Vposition.
3. Move lead “A” to 380-415 Terminal.
380,400 or 415 VAC 1. Open reconnect panel(Codes 11115 and access door on wrap-around.11116) 2. Move input voltage switch
to Voltage = 380-460Vposition.
3. Move lead “A” to 380-415 Terminal.
220 or 230 VAC 1. Open reconnect panel (Codes 11092 and access door on wrap-around.below) 2. Move input voltage switch
to Voltage = 200 -230V position.
3. Move lead “A” to 220-230 Terminal.
200 or 208 VAC 1. Open reconnect panel (Codes 11092 and access door on wrap-around.below) 2. Move input voltage switch
to Voltage = 200 -230V position.
3. Move lead “A” to 200-208 Terminal.
200 or 208 VAC 1. Open reconnect panel (Codes 11115 and access door on wrap-around.11116) 2. Move input voltage switch
to Voltage = 200 -230V position.
3. Move lead “A” to 200-208 Terminal.
OUTPUT CONNECTIONS
WIRE FEEDER OUTPUT CONNECTIONS
Refer to the Accessories section of this manual forinstructions on connecting a wire feeder to the InvertecSTT II.
The LN-742 or STT-10 wire feeder is the recommend-ed feeder for use with the Invertec STT II.
WARNING
4A380-415 OR
OR200-208
*
*
*(NOT PRESENT ON ALL MODELS)
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Section B-1 Section B-1
INVERTEC STT
TABLE OF CONTENTS- OPERATION SECTION -
Operation...............................................................................................................................Section B
Safety Precautions ......................................................................................................................B-2
General Description ....................................................................................................................B-3
Recommended Equipment..........................................................................................................B-3
Operating Controls ......................................................................................................................B-3
Design Features..........................................................................................................................B-3
Welding Capability ......................................................................................................................B-3
Limitations ...................................................................................................................................B-3
Operational Features and Controls.............................................................................................B-4
Welding Operation ......................................................................................................................B-5
Welding Parameters and Guidelines ..........................................................................................B-6
Recommended Settings for STT II..............................................................................................B-7
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B-2 B-2
INVERTEC STT
ELECTRIC SHOCKcan kill.
• Do not touch electrically live partsor electrode with skin or wetclothing.
• Insulate yourself from work andground.
• Always wear dry insulating gloves.
FUMES AND GASEScan be dangerous.
• Keep your head out of fumes.
• Use ventilation or exhaust toremove fumes from breathingzone.
WELDING SPARKScan cause fire orexplosion
• Keep flammable material away.
• Do not weld on containers thathave held combustibles.
ARC RAYScan burn.
• Wear eye, ear and bodyprotection.
OPERATING INSTRUCTIONS
Read and understand entire section beforeoperating machine.
GENERAL WARNINGS
SAFETY PRECAUTIONS
Observe additional Safety Guidelines detailed in the beginning of this manual.
WARNING
OPERATION
OPERATIONB-3 B-3
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The Invertec STT II is a 225-ampere inverter based arcwelding power source specifically designed for the STTwelding process. It is neither a constant current (CC)nor a constant voltage (CV) machine. It is a powersource that delivers current of a desired wave form andcharacteristics that are superior to conventional shortcircuiting GMAW. The process is optimized for short-circuiting GMAW welding.
RECOMMENDED EQUIPMENT
The LN-742 or STT-10 wire feeder is recommended foruse with the STT II. The LN-7 GMA, LN-9 GMA, NA-5,and NA-5R can all be used with the STT II. However,these units can only be used to feed wire since thesefeeders have no provision for control of the STT output.
OPERATING CONTROLS
The Invertec STT II has the following controls as stan-dard: On/Off switch, Peak Current adjustment,Background Current adjustment, Hot Start adjustment,Tailout, and 2 toggle switches; one for wire size selec-tion and one for wire type selection.
DESIGN FEATURES AND ADVANTAGES
• State of the art inverter technology yields high powerefficiency, excellent welding performance, light-weight and compact design.
• Twist-Mate™ output terminals.
• Digital meters for procedure settings are standard.
• Automatic Inductance or Pinch Control.
• Solid state circuitry for extra long component life.
• Current feedback ensures that original proceduresettings all remain constant.
• Arc Sense lead assembly (Electrode and Work),connects through a 4-pin case front connector.
• Peak Current and Background Current may beremotely controlled.
• Thermostat and FET over current protector preventoverheating from overloads, high ambient tempera-tures, or loss of air flow.
• High temperature Class H insulation.
• Protection circuits and ample safety margins preventdamage to the solid state components from transientvoltages and high currents.
• Preset welding current capability.
• STT II offers improvements over the previous model.Approximately 40% increase in deposition rate capa-bility, and a significant increase in travel speed.
WELDING CAPABILITY
The Invertec STT II is rated at 225 amps, 29 volts, at60% duty cycle on a ten minute basis. It is capable ofhigher duty cycles at lower output currents. If the dutycycle(s) are exceeded, a thermal protector will shut offthe output until the machine cools to a reasonableoperating temperature.
LIMITATIONS
• May not be suitable for use in an environment withHigh Frequency present. (“See Machine Groundingand High Frequency Protection” in the Installationsection of this manual)
• Suitable for indoor use only (IEC IP21S).
OPERATIONB-4 B-4
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1. POWER SWITCH: Turns outputpower ON and OFF. This switchalso controls auxiliary poweravailable through the 14-pin WireFeeder Receptacle.
2A. BACKGROUND CURRENT OUTPUT CONTROL:The output current is switched to theBackground level at the conclusion of thepreceding Peak Current pulse. This knoballows preset adjustment of the amplitudeof the background current up to 125amperes.
2B. BACKGROUND CURRENT DISPLAY METER:This is a digital meter for displaying thepreset Background Current. This meterdisplays in 1 amp increments. This meterdoes not indicate the actual welding cur-rent, only the preset current.
3A. PEAK CURRENT OUTPUT CONTROL: Thebeginning portion of the welding arc is apulse of current referred to as PeakCurrent. This knob allows preset adjust-ment of the amplitude of the peak currentup to 450 amperes.
3B. PEAK CURRENT DISPLAY METER: Thisis a digital meter for displaying the presetPeak Current. This meter displays in 1amp increments. This meter does not indi-cate actual welding current only the presetcurrent.
4. HOT START CONTROL POTENTIOMETER:“Hot Start” provides approximately 25% to50% more current during the initial start ofthe weld for improved arc starting and beadappearance. This control adjusts the dura-tion of this “Hot Start” current. The control range isfrom 0 to 10, where 0 corresponds to the zero or no“Hot Start”, and 10 is maximum for a “Hot Start” last-ing for about four (4) seconds.
5. TAILOUT: Alters the current waveform to increasedeposit rate and travel speed. The Minimum settingsets STT II to the original STT waveform. As tailoutis increased peak and Background current mayneed to be reduced to maintain optimum perfor-mance.
OPERATIONAL FEATURES AND CONTROLS
All operator controls are located on the case front of the Invertec STT II. Refer to Figure B.1 for locations.
FIGURE B.1 CASE FRONT CONTROLS
4
1
23
7
6
8
10
9
11
14
15 12
13
5
ON
OFF
A
AV
OPERATIONB-5 B-5
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6. WIRE SIZE SELECT SWITCH: This toggle switchselects between electrode diameters of .035” (1 mm)and smaller or .045” (1.2 mm) and larger. The .035”(1 mm) position provides improved performance ofsmaller diameter wires at higher wire feed speeds.
7. WIRE TYPE SELECT SWITCH: This toggle switchselects between mild or stainless steel. In the stain-less position, the pulse width of the Peak Current ischanged from 1 to 2 ms for better performance forstainless steel welding.
8. THERMAL SHUT-DOWN INDICATOR: This lightwill indicate that either the internal thermo-stat(s) or the FET over current sensor hasactuated. Machine output will return afterthe internal components have returned to normaloperating temperature (if the thermostat(s)“opened”) or after about 3-7 seconds (if the FET overcurrent sensor activated).
9. REMOTE RECEPTACLE: This is a 10 pin MS-typeconnector for remote control of Peak Current andBackground Current. Trigger switch connectionsare also provided. The presence of the mating con-nector is automatically sensed, disabling the front panel Peakand Background Current controls. Refer to “REMOTE CON-TROL CONNECTOR” in the ACCESSORIES Section of thismanual for more information.
10. WIRE FEEDER RECEPTACLE: This is 14pin MS-type connector for the wire feederconnection. 115 and 42 VAC along withthe trigger switch connections are provid-ed. (Only 42 VAC is available on European mod-els). There are no provisions for voltage control ofthe power source by the wire feeder. Refer to theAccessories section of this manual for wire feederconnection instructions.
11. ARC SENSE RECEPTACLE: This is a four pin MS-type connector for WORK and ELECTRODE senseleads. The STT requires a WORK sense and ELEC-TRODE sense lead for proper operation. TheELECTRODE sense lead is bolted together withpower source electrode lead at the wire feeder gunblock. The WORK sense lead is furnished with an“alligator” type clip for connection to the work piece.Refer to the LN 742 or STT-10 wire feeder connec-tion instructions in the Accessories section of thismanual for proper connection of these leads.
12. 42V AUXILIARY POWER CIRCUIT BREAKER:The 42 VAC supply is protected from excessive currentdraws with a 6 amp circuit breaker. When thebreaker “trips” its button will extend.Depressing this button will reset the breaker.
13. 115V AUXILIARY POWER CIRCUIT BREAKER(Not on European Models): The 115 VACsupply is protected from excessive currentdraws with a 6 amp circuit breaker. Whenthe breaker “trips” its button will extend.Depressing this button will reset the breaker.
14. WORK TERMINAL: This twist-mate con-nection is the negative output terminal forconnecting a work cable and clamp to theworkpiece.
15. ELECTRODE TERMINAL: This twist-mateconnection is the positive output terminalfor connecting an electrode cable to thewire feeder conductor block. Refer to theAccessories Section for wire feeder connectioninstructions.
WELDING OPERATION
Familiarize yourself with the controls on the InvertecSTT II before beginning to weld.
Familiarize yourself with the operating manual for thewire feeder and the wire feeder controls before begin-ning to weld.
Set the Wire Size and Wire Type selection switches perthe appropriate wire. Refer to “Operational Featuresand Controls” in this section for the function of theseswitches.
OPERATIONB-6 B-6
INVERTEC STTRet
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LINES
The Invertec STT II is neither a constant current (CC)nor a constant voltage (CV) power source. In general,wire diameter will be increased one size compared toconventional (CV) power sources. The larger the wirediameter the higher the deposition rate (Up to 1/16”).Wire sizes below .035” are unnecessary for most appli-cations. The Invertec STT II is a current controlledmachine which is capable of changing the electrodecurrent quickly in order to respond to the instantaneousrequirements of the arc and optimize performance.By sensing changes in welding current, and hence theelectrode state, the power source will supply varyingoutput currents to minimize spatter. The Peak andBackground currents are two such current outputs thatcan be adjusted.
Wire Feed Speed controls the deposition rate. PeakCurrent controls the Arc Length. Background Currentcontrols the Bead Contour. And Tailout increasesPower in the Arc.
PEAK CURRENTThe Peak Current control acts similar to an “arc pinch”control. Peak current serves to establish the arc lengthand promote good fusion. Higher peak current levelswill cause the arc to broaden momentarily whileincreasing the arc length. If set too high, globular typetransfer will occur. Setting this level to low will causeinstability and wire stubbing. In practice, this currentlevel should be adjusted for minimum spatter and pud-dle agitation.
Adjust Arc Length with Peak Current
Note: In 100% CO2 shielding gas applications the peakcurrent level should be set greater than in a corre-sponding application using a gas blend with a high per-centage of Argon. Longer initial arc lengths with 100%CO2 are required to reduce spatter.
BACKGROUND CURRENTThe Background Current provides the control for theoverall heat input to the weld. Adjusting this level toohigh will cause a large droplet to form and globular typetransfer to occur resulting in increased spatter.
Adjusting this level to low will cause wire stubbing andalso poor wetting of the weld metal. This is similar to alow voltage setting on a standard CV machine
Adjust Bead Shape using Background Current
Note: Background Current levels for applications using100% CO2 is less than similar procedures involving gasblends with high percentages of Argon. This is a resultof the greater heat generated in the 100% CO2 arc.(100% CO2 is 35 volts/cm and 100% Argon is 20volts/cm. 75% Argon, 25% CO2 is about 24 volts/cm.
Contact Tip to Work Distance
HOT STARTThe Hot Start control can be set to enhance establish-ing the arc and provide the capability of increasing theheat at the start of the weld to compensate for a coldwork piece. Hot start adjusts the time that additionalcurrent is applied during the starting of the arc. Refer to“Operational Features and Controls” in this sectionfor a description of this control.
TAILOUTThe tail out provides additional heat without the moltendroplet becoming too large. Increase as necessary toadd “Heat” to the arc without increasing arc length.(This will allow for faster travel speeds and produceimproved wetting). As tailout is increased, the pealand/or background current is usually reduced.
WELDING ARC PERFORMANCEFor optimum spatter reduction, the arc should be con-centrated on the puddle.
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OPERATIONB-7 B-7
INVERTEC STT
WELDING PROCEDURES FOR STT II -(Steel) Horizontal Fillet (See Table B.1 and B.2)
Table B.1 100% CO2 Gas Shield (Set for Steel Mode)
Table B.2 75% CO2 - 25% Ar Gas Shield (Set for Steel Mode)
(Stainless Steel) Horizontal Fillet(See Table B.3 and B.4)
Table B.3 90% He, 7.5% Ar, 2.5% CO2
Gas Shield (Set for Steel Mode)
Table B.4 98% Ar, 2% O2
Gas Shield (Set for Stainless Steel Mode)
45°
END VIEW
75°
FRONT VIEW
DIRECTIONOF
TRAVEL
75°
TOP VIEW
DIRECTIONOF
TRAVEL
Plate Thickness “ (mm) 20 ga 14 ga 10 ga(0.9) (2.0) (3.25)
Electrode size “ (mm) 0.035 0.045 0.045(0.9) (1.1) (1.1)
WFS “/min (m/min) 100 100 170(2.5) (2.5) (4.2)
Peak Current 220 260 280Background Current 30 40 65Tailout setting 3 7 5Average Amperage 60 105 120Travel Speed “/min 12 12 12
(m/min) (0.3) (0.3) (0.3)Gas Flow cfh (L/min) 25 (12)Electrical Stickout “ 1/4 - 3/8
(mm) (6.4 - 10)
Plate Thickness “ (mm) 20 ga 14 ga 10 ga(0.9) (2.0) (3.25)
Electrode size “ (mm) 0.035 0.045 0.045(0.9) (1.1) (1.1)
WFS “/min (m/min) 100 100 120(2.5) (2.5) (3.0)
Peak Current 225 270 310Background Current 40 65 70Tailout setting 8 4 6Average Amperage 70 110 130Travel Speed “/min 12 12 12
(m/min) (0.3) (0.3) (0.3)Gas Flow cfh (L/min) 25 (12)Electrical Stickout “ 1/4 - 3/8
(mm) (6.4 - 10)
45°
END VIEW
75°
FRONT VIEW
DIRECTIONOF
TRAVEL
75°
TOP VIEW
DIRECTIONOF
TRAVEL
Plate Thickness “ (mm) 20 ga 14 ga 10 ga(0.9) (2.0) (3.25)
Electrode size “ (mm) 0.035 0.045 0.045(0.9) (1.1) (1.1)
WFS “/min (m/min) 100 130 170(2.5) (3.3) (4.2)
Peak Current 165 210 250Background Current 35 60 85Tailout setting 7 7 4Average Amperage 40 95 120Travel Speed “/min 12 16 16
(m/min) (0.3) (0.4) (0.4)Gas Flow cfh (L/min) 25 (12)Electrical Stickout “ 1/4 - 3/8
(mm) (6.4 - 10)
Plate Thickness “ (mm) 20 ga 14 ga 10 ga(0.9) (2.0) (3.25)
Electrode size “ (mm) 0.035 0.045 0.045(0.9) (1.1) (1.1)
WFS “/min (m/min) 100 130 170(2.5) (3.3) (4.2)
Peak Current 145 190 280Background Current 45 95 95Tailout setting 7 8 7Average Amperage 60 120 150Travel Speed “/min 12 12 12
(m/min) (0.3) (0.3) (0.3)Gas Flow cfh (L/min) 25 (12)Electrical Stickout “ 1/4 - 3/8
(mm) (6.4 - 10)
NOTESB-8 B-8
INVERTEC STTRet
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OC TABLE OF CONTENTS
- ACCESSORIES -Accessories...........................................................................................................................Section C
Options/Accessories ...................................................................................................................C-2
LN-742 Wire Feeder Connection Instructions.............................................................................C-3
Connection Diagram ...................................................................................................................C-4
Section C-1 Section C-1
INVERTEC STT
ACCESSORIESC-2 C-2
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STT control board to accept PEAK and BACK-GROUND inputs on this connector rather than fromthe front panel controls. If this short is removed, thefront panel controls will be active. By adding a switchbetween pins “J” and “B” a “LOCAL/REMOTE” con-trol switch can be created. (Switch open for “local”and closed for “remote”)
3. For robotic control of the PEAK CURRENT, a 0 to+10 volt DC signal is applied between pins “A” and“G” with + applied to pin “G”. The BACKGROUNDCURRENT is controlled with a similar signal appliedbetween pins “A” and “C” with + applied to pin “C”.In this application pins “J” and “B” must be shortedas described in 2 above.
NOTE: These analog signals should be isolatedfrom the robot circuitry to prevent interference.
4. The trigger switch is connected between pins “D”and “F”. These connections are in parallel with thetrigger switch from the wire feeder.
5. The digital meters for PEAK and BACKGROUNDcurrents will show preset values in both local andremote operation.
OPTIONS / ACCESSORIES
K940 SENSE LEADS: These leads are used to accu-rately sense arc voltage. One set is required for eachSTT II power source. A 10 ft and 25 ft set are provid-ed as standard with the machine. Additional sets areavailable in 10 ft (K940-10), 25 ft (K940-25) and 50 ft(K940-50) lengths.
K942-1 REMOTE CONTROL: Allows remote adjust-ment of Peak and Background Current settings.
REMOTE RECEPTACLE (For optional remote interface,Connection to the STT-10 Wire Feeder or Robotic Control)
1. The 10 pin MS connector labeled “Remote Control”located on the front panel of the STT is used forremote control of the power source. Control for thePEAK (PB pot) and BACKGROUND (BG pot) cur-rent along with the trigger switch is provide throughthis connector.
2. Refer to figure C.1 below for details about theremote receptacle (J38). Note that pins “J” and “B”are shorted together This “short circuit” tells the
+ ARC
- ARC
12
34
VOLTAGE
SENSE
CONNECTION
J19
290
291
(+)
(-)
J
B
CGA
D
FHEI
TRIGGER
GND
BG
PB
10K
10K
OPTIONALREMOTEINTERFACE223
7
J38
33C
1
23
4
J37
8
61
584
32
212C
43A
212B32C
3
12
109
12411
J38
REMOTEPROTECTION BOARD
PORTION OF G3136 WIRING DIAGRAMREFER TO ACTUAL DIAGRAM PASTED INSIDE YOUR MACHINE
N ELECTRODE SENSE LEAD
290A
J39
WIRE
FEEDER
ACCESSORIESC-3 C-3
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CONNECTION INSTRUCTIONS
The LN-742 or STT-10 is the recommended wire feed-er for use with the Invertec STT II. Refer to the LN-742 or STT-10 Operator Manual for Wire FeedOperation. Refer to Figure C.2 or C.3 and follow theinstructions below to connect the LN-742 or STT-10.
1. Turn the Invertec STT II power off.
2. Connect the ARC SENSE LEAD MS connector tothe mating connector on STT II front panel.
3. Connect the electrode lead (Twist-Mate) to (+) out-put terminal on STT II.
4. Connect the other end of electrode lead (Step #3)and the ARC SENSE LEAD (lead with ring lug, step#2) together to the gun block on the LN 742.
5. Connect work lead between STT (-) terminal and thework piece.
6. Connect the ARC SENSE LEAD “WORK” (lead withalligator clip) to work piece.
NOTE: For best welding performance make thisconnection as close as possible to thewelding arc.
7. Connect the wire feeder control cable between theLN-742 or STT-10 and the 14-pin Wire FeederReceptacle on the STT II. For the STT-10 WireFeeder: Connect the second wire feeder controlcable between the STT-10 and the 10-pin RemoteReceptacle on the STT II.
M17657
ARC SENSE LEAD
’ELECT"
CONNECT ELECTRODE LEAD AND "ELECT"ARC SENSE LEAD TOGETHER TO ELECTRODETERMINAL OF WIRE FEEDER.
ELECTRODE LEAD
Only qualified persons should install,
use or service this machine.
WIRE FEEDERLN 742LN7 GMALN9 GMANA5RNA5
WARNING
ELECTRIC
SHOCK
CAN KILL
Turn off input power to the Welding
Power source using the disconnnect
switch at the fuse box before
connecting the wire feeder.
REMOTE RECEPTACLE
WORK
WORK LEAD
CONTROL, ELECTRODE, ARC SENSE "ELECT"AND ARC SENSE "WORK" CABLES SHOULD
BE TAPED TOGETHER.
WIRE FEEDERCONTROL CABLE
ARC SENSE LEAD "WORK"
(SHOULD BE LOCATED
AS CLOSE AS POSSIBLE
TO THE WELDING ARC.) CRM after 6-10-96
FIGURE C.2 LN-742 to STT II CONNECTION
WARNING
ELECTRIC SHOCK can kill.• Only qualified personnel should perform
this installation.
• Turn the input power OFF at the discon-nect switch or fuse box before connectingthe wire feeder
C-4 C-4
INVERTEC STTRet
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ACCESSORIES CONNECTION DIAGRAM - INVERTEC STT II
4-9-99
M17657-3
CABLES AND LEADS SHOULD
ELECTRODE LEAD
BE TAPED TOGETHER.
WORK (SHOULD BE LOCATED
AS CLOSE AS POSSIBLE
FEEDER
REMOTE
REMOTE
ELECTRODE LEAD
TO THE WELDING ARC)
WORK LEAD
WIRE FEEDER
WIRE FEEDER CONTACT
ELECTRODE SENSE LEAD
IS BOLTED TOGETHER WITH
ELECTRODE LEAD ON THE
BLOCK
STT-10WIRE FEEDER
WARNING Turn off input power to the Welding
Power source using the disconnnect
switch at the fuse box before
connecting the wire feeder.
Only qualified persons should install,ELECTRICuse or service this machine. SHOCK
CAN KILL
WIRE
ARC SENSE LEAD "WORK"
FIGURE C.3 STT-10 to STT II CONNECTION
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Section D-1 Section D-1
INVERTEC STT
TABLE OF CONTENTS-MAINTENANCE-
Maintenance .........................................................................................................................Section D
Input Filter Capacitor Discharge Procedure................................................................................D-2
Preventive Maintenance .............................................................................................................D-3
Major Component Locations.......................................................................................................D-4
MAINTENANCED-2 D-2
INVERTEC STTRet
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Failure to follow thiscapacitor discharge proce-dure can result in electricshock.
INPUT FILTER CAPACITORDISCHARGE PROCEDURE
1. Turn off input power or disconnect inputpower lines.
2. Remove hex head screws from side andtop of machine and remove wrap-aroundmachine cover.
3. Be careful not to make contact with thecapacitor terminals that are located in thecenter of the Switch Boards.
4. Obtain a high resistance and highwattage resistor (25-1000 ohms and 25watts minimum). This resistor is not sup-plied with machine. NEVER USE ASHORTING STRAP FOR THIS PROCE-DURE.
5. Locate the two capacitor terminals (largehex head cap screws) shown in Figure D.1.
6. Use safety glasses, electrically insulatedgloves and insulated pliers. Hold body ofthe resistor and connect resistor leadsacross the two capacitor terminals. Holdresistor in place for 10 seconds. DO NOTTOUCH CAPACITOR TERMINALS WITHYOUR BARE HANDS.
7. Repeat discharge procedure for capaci-tor on other side of machine.
8. Check voltage across terminals of allcapacitors with a DC voltmeter. Polarityof capacitor terminals is marked on PCboard above terminals. Voltage should bezero. If any voltage remains, repeat thiscapacitor discharge procedure.
FIGURE D.1 — LOCATION OF INPUT FILTER CAPACITOR TERMINALS.
MAINTENANCED-3 D-3
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PREVENTIVE MAINTENANCE
1. Perform the following preventive mainte-nance procedures at least once every sixmonths. It is good practice to keep a pre-ventive maintenance record; a record tagattached to the machine works best.
2. Remove the machine wraparound coverand perform the input filter capacitor dis-charge procedure (detailed at the begin-ning of this chapter).
3. Clean the inside of the machine with alow pressure airstream. Be sure to cleanthe following components thoroughly.
• Power Switch, Driver, Protection, andControl printed circuit boards
• Power Switch
• Main Transformer
• Input Rectifier
• Heat Sink Fins
• Input Filter Capacitors
• Output Terminals
• Lower base compartment
4. Examine capacitors for leakage or oozing.Replace if needed.
5. Examine wraparound cover for dents orbreakage. Repair as needed. Cover mustbe kept in good condition to assure highvoltage parts are protected and correctspacings are maintained.
6. Check electrical ground continuity. Usingan ohmmeter, measure resistancebetween either output stud and an unpaint-ed surface of the machine case. Meterreading should be 500,000 ohms or more.If meter reading is less than 500,000ohms, check for electrical components thatare not properly insulated from the case.Correct insulation if needed.
7. Replace machine cover and screws.
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MAINTENANCED-4 D-4
INVERTEC STT
12
4
17
5
69
8
7
10
16
15
1318
14
19
11
1
3
2
FIGURE D.2 – MAJOR COMPONENT LOCATIONS
1. BASE ASSEMBLY2. REAR NAMEPLATE3. RESISTORS4. FAN SHROUD ASSEMBLY5. PROTECTION PC BOARD6. DRIVER PC BOARD7. CONTROL BOX8. CONTROL PC BOARD9. BLEEDER RESISTORS
10. RECONNECT PANEL11. IGBT OR DARLINGTON MODULE12. WRAPAROUND ASSEMBLY13. CASE FRONT ASSEMBLY14. OUTPUT TERMINALS15. OUTPUT CHOKE ASSEMBLY16. TRANSFORMER ASSEMBLY17. OUTPUT RECTIFIER ASSEMBLY18. AUXILIARY TRANSFORMER19. FET HEAT SINK ASSEMBLY
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Section E-1 Section E-1
INVERTEC STT
Theory of Operation .............................................................................................................Section E
General Description ...............................................................................................................E-2
Input Voltage..........................................................................................................................E-2
Reconnect, Protection Board, Rectification and Precharge ..................................................E-3
Switch Boards........................................................................................................................E-4
Main Transformer, Output Rectification and Choke...............................................................E-5
Control Board, IGBT Drive and Module.................................................................................E-6
Power Board ..........................................................................................................................E-7
Remote Protection Board ......................................................................................................E-7
Field Effect Transistor (FET) Operation.................................................................................E-8
Pulse Width Modulation.........................................................................................................E-9
Minimum Output ..............................................................................................................E-9
Maximum Output .............................................................................................................E-9
Protective Circuits................................................................................................................E-10
Overload Protection.......................................................................................................E-10
Thermal Protection ........................................................................................................E-10
TABLE OF CONTENTS-THEORY OF OPERATION SECTION-
POSITIVEOUTPUT
TERMINAL
TERMINALOUTPUT
NEGATIVE
CONTROL BOARDIGBT
DRIVERBOARD
POWER
BOARD
FAN TRANST1
TRANST4
SWITCH
BOARD
SWITCH
BOARD
RECONNECT
PROTECTION
INPUTRECTIFIER
LINESWITCH
CR1
CR2
BOARD
DRI
VER
BOARD
PRE - CHARGE
PRE - CHARGE
CHOKE
CURRENTSENSOR
IGBTMODULE
1 OHM
PEAKCURRENT
METER
BACK-
METERPEAK
CURRENTCONTROL
BACK-
CONTROL
HOT START
CONTROL
WIRESIZE
SWITCH
WIRETYPE
SWITCH
VOLTAGESENSING
RECEPTACLE
REMOTECONTROL
RECEPTACLE
WIRE
RECEPTACLEFEEDER
REMOTE
PROTECTION
BOA
R
D
CURRENTTRANS
T3
MAIN TRANSFORMER
T2
115VAC
18VAC
24VAC
"A"LEAD
15VDC
THERMOSTAT
CURRENT FEEDBACK
42VAC
VOLTAGE FEEDBACK
10VAC AND 6VAC
DRIVE
SIGNAL
36VAC
GUN TRIGGER
LESS THAN 1VDC
PWM SIGNAL
PULSE TRANSFORMER SIGNAL
GROUND GROUND
FET
FET
FET
FET
CAP
CAP
TAILOUTCONTROL
(STT II ONLY)
FIGURE E.1 – INVERTEC STT
GENERAL DESCRIPTIONThe Invertec STT is a 225 ampere, inverter based, arcwelding power supply specifically designed for theSurface Tension Transfer (STT) welding process. Itcannot be classified as either a constant current (CC)or a constant voltage (CV) machine. The STT pro-duces current of a desired waveform to reduce spatterand fumes. The STT process is optimized for short -circuit GMAW welding only.
INPUT VOLTAGEThe Invertec STT can be connected for a variety ofthree-phase voltages. The initial input power is appliedto the STT through a line switch located on the front ofthe machine. The AC input voltage is applied to theinput rectifier and the T1 auxiliary transformer. The T1transformer develops the appropriate AC voltages tooperate the cooling fan, the power and control boards.The T1 transformer also supplies primary voltage to theT4 auxiliary transformer as well as 42 VAC to an exter-nal wire feeder. The T4 transformer supplies power tothe IGBT drive board and the control board.
THEORY OF OPERATIONE-2 E-2
INVERTEC STTRet
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NOTE: Unshaded areas of Block Logic Diagram are the subject of discussion.
POSITIVEOUTPUT
TERMINAL
TERMINALOUTPUT
NEGATIVE
CONTROL BOARDIGBT
DRIVERBOARD
POWER
BOARD
FAN TRANST1
TRANST4
SWITCH
BOARD
SWITCH
BOARD
RECONNECT
PROTECTION
INPUTRECTIFIER
LINESWITCH
CR1
CR2
BOARD
DRI
VER
BOARD
PRE - CHARGE
PRE - CHARGE
CHOKE
CURRENTSENSOR
IGBTMODULE
1 OHM
PEAKCURRENT
METER
BACK-
METERPEAK
CURRENTCONTROL
BACK-
CONTROL
HOT START
CONTROL
WIRESIZE
SWITCH
WIRETYPE
SWITCH
VOLTAGESENSING
RECEPTACLE
REMOTECONTROL
RECEPTACLE
WIRE
RECEPTACLEFEEDER
REMOTE
PROTECTION
BOA
R
D
CURRENTTRANS
T3
MAIN TRANSFORMER
T2
115VAC
18VAC
24VAC
"A"LEAD
15VDC
THERMOSTAT
CURRENT FEEDBACK
42VAC
VOLTAGE FEEDBACK
10VAC AND 6VAC
DRIVE
SIGNAL
36VAC
GUN TRIGGER
LESS THAN 1VDC
PWM SIGNAL
PULSE TRANSFORMER SIGNAL
GROUND GROUND
FET
FET
FET
FET
CAP
CAP
TAILOUTCONTROL
(STT II ONLY)
RECONNECT, PROTECTIONBOARD, RECTIFICATION ANDPRECHARGEThe reconnect panel allows the user to switch to low orhigh input voltage to match the input line voltage. TheAC input voltage is rectified and applied to the driverboard. The driver board contains precharging circuitryfor safe charging of the input filter capacitors. Once thecapacitors are precharged, the input relays are ener-gized, connecting full input power to the input filtercapacitors. The protection board monitors the capaci-tors for voltage balance and/or overvoltage and will de-energize the input relays and precharge circuitry ifeither occurs. The machine output will be disabled.
THEORY OF OPERATIONE-3 E-3
INVERTEC STTRet
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NOTE: Unshaded areas of Block Logic Diagram are the subject of discussion.
FIGURE E.3 – RECONNECT, PROTECTION BOARD, RECTIFICATION AND PRECHARGE
POSITIVEOUTPUT
TERMINAL
TERMINALOUTPUT
NEGATIVE
CONTROL BOARDIGBT
DRIVERBOARD
POWER
BOARD
FAN TRANST1
TRANST4
SWITCH
BOARD
SWITCH
BOARD
RECONNECT
PROTECTION
INPUTRECTIFIER
LINESWITCH
CR1
CR2
BOARD
DRI
VER
BOARD
PRE - CHARGE
PRE - CHARGE
CHOKE
CURRENTSENSOR
IGBTMODULE
1 OHM
PEAKCURRENT
METER
BACK-
METERPEAK
CURRENTCONTROL
BACK-
CONTROL
HOT START
CONTROL
WIRESIZE
SWITCH
WIRETYPE
SWITCH
VOLTAGESENSING
RECEPTACLE
REMOTECONTROL
RECEPTACLE
WIRE
RECEPTACLEFEEDER
REMOTE
PROTECTION
BOA
R
D
CURRENTTRANS
T3
MAIN TRANSFORMER
T2
115VAC
18VAC
24VAC
"A"LEAD
15VDC
THERMOSTAT
CURRENT FEEDBACK
42VAC
VOLTAGE FEEDBACK
10VAC AND 6VAC
DRIVE
SIGNAL
36VAC
GUN TRIGGER
LESS THAN 1VDC
PWM SIGNAL
PULSE TRANSFORMER SIGNAL
GROUND GROUND
FET
FET
FET
FET
CAP
CAP
TAILOUTCONTROL
(STT II ONLY)
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THEORY OF OPERATIONE-4 E-4
INVERTEC STT
NOTE: Unshaded areas of Block Logic Diagram are the subject of discussion.
FIGURE E.4 – SWITCH BOARDS
SWITCH BOARDSThere are two switch boards in the Invertec STT, eachcontaining an input filter capacitor. The capacitors areconnected in parallel when the machine is connectedfor "low" input voltage. The capacitors are connectedin series when the reconnect switch is configured for"high" input voltage. When the capacitors are fullycharged, they act as power supplies for the switchboards. The switch boards contain the Field EffectTransistors (FETs) which, when switched on, supplythe main transformer primary windings with DC currentflow. See Field Effect Transistor (FET) Operationdiscussion and diagrams. See Figure E.4.
POSITIVEOUTPUT
TERMINAL
TERMINALOUTPUT
NEGATIVE
CONTROL BOARDIGBT
DRIVERBOARD
POWER
BOARD
FAN TRANST1
TRANST4
SWITCH
BOARD
SWITCH
BOARD
RECONNECT
PROTECTION
INPUTRECTIFIER
LINESWITCH
CR1
CR2
BOARD
DRI
VER
BOARD
PRE - CHARGE
PRE - CHARGE
CHOKE
CURRENTSENSOR
IGBTMODULE
1 OHM
PEAKCURRENT
METER
BACK-
METERPEAK
CURRENTCONTROL
BACK-
CONTROL
HOT START
CONTROL
WIRESIZE
SWITCH
WIRETYPE
SWITCH
VOLTAGESENSING
RECEPTACLE
REMOTECONTROL
RECEPTACLE
WIRE
RECEPTACLEFEEDER
REMOTE
PROTECTION
BOA
R
D
CURRENTTRANS
T3
MAIN TRANSFORMER
T2
115VAC
18VAC
24VAC
"A"LEAD
15VDC
THERMOSTAT
CURRENT FEEDBACK
42VAC
VOLTAGE FEEDBACK
10VAC AND 6VAC
DRIVE
SIGNAL
36VAC
GUN TRIGGER
LESS THAN 1VDC
PWM SIGNAL
PULSE TRANSFORMER SIGNAL
GROUND GROUND
FET
FET
FET
FET
CAP
CAP
TAILOUTCONTROL
(STT II ONLY)
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THEORY OF OPERATIONE-5 E-5
INVERTEC STT
FIGURE E.5 – MAIN TRANSFORMER, OUTPUT RECTIFICATION AND CHOKE
MAIN TRANSFORMER, OUTPUTRECTIFICATION AND CHOKEEach switch board works as a switch pair. Each boardfeeds a separate, oppositely wound primary winding ofthe main transformer. The opposite directions of cur-rent flow through the main transformer primary and theoffset timing of the switch boards induce an AC squarewave output signal at the secondary of the main trans-former.
The DC current flow through each primary winding,which is monitored by the current transformer T3, isredirected or "clamped" back to each respective inputcapacitor when the FETs are turned off. This is need-ed due to the inductance of the transformer primarywindings. The cross coupling of the primaries alongwith the clamping action of the diode maintain capaci-tor balance when they are connected in the series (highvoltage) input configuration.
The firing of both switch board pairs occurs duringhalves of 50 microsecond intervals, creating a constant20 KHZ output.
The AC output from the main transformer secondary isrectified to a DC output and is applied through a stabi-lizer output choke, current sensor, IGBT module andremote protection board to the output terminals.
NOTE: Unshaded areas of Block Logic Diagram are the subject of discussion.
POSITIVEOUTPUT
TERMINAL
TERMINALOUTPUT
NEGATIVE
CONTROL BOARDIGBT
DRIVERBOARD
POWER
BOARD
FAN TRANST1
TRANST4
SWITCH
BOARD
SWITCH
BOARD
RECONNECT
PROTECTION
INPUTRECTIFIER
LINESWITCH
CR1
CR2
BOARD
DRI
VER
BOARD
PRE - CHARGE
PRE - CHARGE
CHOKE
CURRENTSENSOR
IGBTMODULE
1 OHM
PEAKCURRENT
METER
BACK-
METERPEAK
CURRENTCONTROL
BACK-
CONTROL
HOT START
CONTROL
WIRESIZE
SWITCH
WIRETYPE
SWITCH
VOLTAGESENSING
RECEPTACLE
REMOTECONTROL
RECEPTACLE
WIRE
RECEPTACLEFEEDER
REMOTE
PROTECTION
BOA
R
D
CURRENTTRANS
T3
MAIN TRANSFORMER
T2
115VAC
18VAC
24VAC
"A"LEAD
15VDC
THERMOSTAT
CURRENT FEEDBACK
42VAC
VOLTAGE FEEDBACK
10VAC AND 6VAC
DRIVE
SIGNAL
36VAC
GUN TRIGGER
LESS THAN 1VDC
PWM SIGNAL
PULSE TRANSFORMER SIGNAL
GROUND GROUND
FET
FET
FET
FET
CAP
CAP
TAILOUTCONTROL
(STT II ONLY)
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THEORY OF OPERATIONE-6 E-6
INVERTEC STT
FIGURE E.6 – CONTROL BOARD, IGBT DRIVE AND MODULE
CONTROL BOARD, IGBT DRIVEAND MODULEThe control board monitors the directives of the variouscontrols and compares these commands to the currentand voltage feedback information received from thecurrent sensor and voltage sensing receptacle. Thisdata is processed and the suitable PWM signal is sentto the power board. (See Pulse Width Modulationdiscussion).
The control board also determines when the IGBTmodule should be switched OFF to reduce weld spat-ter and fumes. The appropriate signal is sent to theIGBT drive board which then applies, or removes, thegate drive signal to the IGBT module. When the IGBTmodule is in the OFF state, the welding current mustpass through the one ohm resistance. This reducesthe current and, subsequently, spatter and fumes.
NOTE: Unshaded areas of Block Logic Diagram are the subject of discussion.
POSITIVEOUTPUT
TERMINAL
TERMINALOUTPUT
NEGATIVE
CONTROL BOARDIGBT
DRIVERBOARD
POWER
BOARD
FAN TRANST1
TRANST4
SWITCH
BOARD
SWITCH
BOARD
RECONNECT
PROTECTION
INPUTRECTIFIER
LINESWITCH
CR1
CR2
BOARD
DRI
VER
BOARD
PRE - CHARGE
PRE - CHARGE
CHOKE
CURRENTSENSOR
IGBTMODULE
1 OHM
PEAKCURRENT
METER
BACK-
METERPEAK
CURRENTCONTROL
BACK-
CONTROL
HOT START
CONTROL
WIRESIZE
SWITCH
WIRETYPE
SWITCH
VOLTAGESENSING
RECEPTACLE
REMOTECONTROL
RECEPTACLE
WIRE
RECEPTACLEFEEDER
REMOTE
PROTECTION
BOA
R
D
CURRENTTRANS
T3
MAIN TRANSFORMER
T2
115VAC
18VAC
24VAC
"A"LEAD
15VDC
THERMOSTAT
CURRENT FEEDBACK
42VAC
VOLTAGE FEEDBACK
10VAC AND 6VAC
DRIVE
SIGNAL
36VAC
GUN TRIGGER
LESS THAN 1VDC
PWM SIGNAL
PULSE TRANSFORMER SIGNAL
GROUND GROUND
FET
FET
FET
FET
CAP
CAP
TAILOUTCONTROL
(STT II ONLY)
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OC
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THEORY OF OPERATIONE-7 E-7
INVERTEC STT
FIGURE E.7 – POWER BOARD AND REMOTE PROTECTION BOARD
POWER BOARDThe power board creates a pulse transformer drive sig-nal, which is derived from the PWM signal receivedfrom the control board. See Pulse Width Modulationdiscussion. This drive signal is applied to the primarywinding of the pulse transformer, which is located onthe driver board. The pulse transformer secondarywindings generate the proper gate pulse for the switchboard FETs. See Field Effect Transistor (FET)Operation.
The power board supplies a 15VDC supply voltage forthe control board and also powers the input relays(CR1 and CR2).
REMOTE PROTECTION BOARDThe remote protection board provides noise suppres-sion and by-pass filtering to protect the internal circuit-ry of the STT machine.
NOTE: Unshaded areas of Block Logic Diagram are the subject of discussion.
POSITIVEOUTPUT
TERMINAL
TERMINALOUTPUT
NEGATIVE
CONTROL BOARDIGBT
DRIVERBOARD
POWER
BOARD
FAN TRANST1
TRANST4
SWITCH
BOARD
SWITCH
BOARD
RECONNECT
PROTECTION
INPUTRECTIFIER
LINESWITCH
CR1
CR2
BOARD
DRI
VER
BOARD
PRE - CHARGE
PRE - CHARGE
CHOKE
CURRENTSENSOR
IGBTMODULE
1 OHM
PEAKCURRENT
METER
BACK-
METERPEAK
CURRENTCONTROL
BACK-
CONTROL
HOT START
CONTROL
WIRESIZE
SWITCH
WIRETYPE
SWITCH
VOLTAGESENSING
RECEPTACLE
REMOTECONTROL
RECEPTACLE
WIRE
RECEPTACLEFEEDER
REMOTE
PROTECTION
BOA
R
D
CURRENTTRANS
T3
MAIN TRANSFORMER
T2
115VAC
18VAC
24VAC
"A"LEAD
15VDC
THERMOSTAT
CURRENT FEEDBACK
42VAC
VOLTAGE FEEDBACK
10VAC AND 6VAC
DRIVE
SIGNAL
36VAC
GUN TRIGGER
LESS THAN 1VDC
PWM SIGNAL
PULSE TRANSFORMER SIGNAL
GROUND GROUND
FET
FET
FET
FET
CAP
CAP
TAILOUTCONTROL
(STT II ONLY)
FIELD EFFECT TRANSISTOR (FET)OPERATIONAn FET is a type of transistor. FETs are semiconduc-tors well suited for high-frequency switching.
Drawing A above shows an FET in a passive mode.There is no gate signal, zero volts relative to the sourceand, therefore, no current flow. The drain terminal ofthe FET may be connected to a voltage supply; butsince there is no conduction, the circuit will not supplycurrent to downstream components connected to thesource. The circuit is turned off like a light switch in theOFF position.
Drawing B above shows the FET in an active mode.When the gate signal, a positive DC voltage relative tothe source, is applied to the gate terminal of the FET, itis capable of conducting current. A voltage supply con-nected to the drain terminal will allow the FET to con-duct and henceforth supply current to downstreamcomponents. Current will flow through the conductingFET to downstream components as long as the gatesignal is present. This is similar to turning on a lightswitch.
THEORY OF OPERATIONSE-8 E-8
INVERTEC STTRet
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SOURCETERMINAL
GATETERMINAL DRAIN
TERMINAL
DRAIN (N)
N CHANNELSUBSTRATE (P)
SOURCE (N)
(0 VOLTS)
GATETERMINAL(+ 6 VOLTS)
DRAIN (N)
ELECTRONS
SOURCE (N)
B. ACTIVE
A. PASSIVE
FIGURE E-8 – FIELD EFFECT TRANSISTOR OPERATION
PULSE WIDTH MODULATIONThe term PULSE WIDTH MODULATION is used todescribe how much time is devoted to conduction inthe positive and negative portions of the cycle.Changing the pulse width is known as MODULATION.Pulse Width Modulation (PWM) is the varying of thepulse width over the allowed range of a cycle to affectthe output of the machine.
MINIMUM OUTPUT
By controlling the duration of the gate signal, the FETis turned on and off for different durations during acycle. The top drawing above shows the minimum out-put signal possible over a 50-microsecond time period.
The positive portion of the signal represents one FETgroup1 conducting for 1 microsecond. The negativeportion is the other FET group1. The dwell time (offtime) is 48 microseconds (both FET groups off). Sinceonly 2 microseconds of the 50-microsecond time peri-od is devoted to conducting, the output power is mini-mized.
MAXIMUM OUTPUT
By holding the gate signals on for 24 microsecondseach and allowing only 2 microseconds of dwell time(off time) during the 50-microsecond cycle, the outputis maximized. The darkened area under the top curvecan be compared to the area under the bottom curve.The more dark area under the curve, the more poweris present.
THEORY OF OPERATIONE-9 E-9
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MINIMUM OUTPUT
MAXIMUM OUTPUT
24
502
4850
secsec
secsec
sec
sec sec
24 sec
FIGURE E-9 – TYPICAL FET OUTPUTS
1 A FET group consists of the sets of FET modules grouped ontoone switch board.
PROTECTIVE CIRCUITSProtective circuits are designed into the Invertecmachine to sense trouble and shut down the machinebefore the trouble damages the internal machine com-ponents. Both overload and thermal protection circuitsare included.
OVERLOAD PROTECTION
The machine is electrically protected from producingabnormally high output currents due to short electrode“stick-out” or the nozzle shorting to the work. Shouldthe output current exceed 500 amps, an electronic pro-tection circuit will reduce the current to zero amps.Five seconds after the “short” is removed the InvertecSTT will produce normal output.
A protection circuit is included to monitor the voltageacross input filter capacitors. In the event that thecapacitor voltage is too high, the protection circuit willprevent output. The protection circuit may prevent out-put, if any of these circumstances occur:
1. Capacitor conditioning is required(Required if machine has been off for prolongedperiods of time.)
2. Line surges over 500 VAC
3. Internal Component damage
4. Improper connections
THERMAL PROTECTION
Thermostats protect the machine from excessive oper-ating temperatures. Excessive temperatures may becaused by a lack of cooling air or operating themachine beyond the duty cycle and output rating. Ifexcessive operating temperature should occur, thethermostat will prevent output voltage or current. Themeter will remain on during this time. (In addition, theyellow thermo LED will light.)
Thermostats are self-resetting once the machine coolssufficiently. If the thermostat shutdown was caused byexcessive output or duty cycle and the fan is operatingnormally, the Power Switch may be left on and thereset should occur within a 15-minute period. If the fanis not turning or the air intake louvers were obstructed,then the power must be switched off for 15 minutes inorder to reset. The fan problem or air obstruction mustalso be corrected.
THEORY OF OPERATIONE-10 E-10
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Section F-1 Section F-1
INVERTEC STT
Troubleshooting & Repair Section ................................................................................Section F
How to Use Troubleshooting Guide.......................................................................................F-2
PC Board Troubleshooting Procedures .................................................................................F-3
Troubleshooting Guide .................................................................................................F4 - F-12
Test Procedures ...................................................................................................................F-13T1 Auxiliary Transformer Test........................................................................................F-13T4 Auxiliary Transformer Test........................................................................................F-19Input Rectifier Test.........................................................................................................F-25Capacitor Balance Test .................................................................................................F-29Switch Board Test..........................................................................................................F-33Snubber Resistors Test .................................................................................................F-37Power Board Test ..........................................................................................................F-41Protection Board Test ....................................................................................................F-45Trigger Circuit Test ........................................................................................................F-49
Replacement Procedures ....................................................................................................F-53IGBT Module Removal and Replacement.....................................................................F-53Switch Board Replacement ...........................................................................................F-59Capacitor Removal and Replacement Procedure.........................................................F-65 Output Rectifier Removal and Replacement.................................................................F-73
Retest After Repair...............................................................................................................F-77
TABLE OF CONTENTSTROUBLESHOOTING & REPAIR SECTION
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HOW TO USE TROUBLESHOOTING GUIDE
Service and repair should be performed by only Lincoln Electric Factory Trained Personnel.Unauthorized repairs performed on this equipment may result in danger to the technician and machineoperator and will invalidate your factory warranty. For your safety and to avoid Electrical Shock, pleaseobserve all safety notes and precautions detailed throughout this manual.
TROUBLESHOOTING & REPAIRF-2 F-2
INVERTEC STT
This Troubleshooting Guide is provided to helpyou locate and repair possible machine malfunc-tions. Simply follow the three-step procedure list-ed below.
Step 1. LOCATE PROBLEM (SYMPTOM). Lookunder the column labeled “PROBLEM (SYMP-TOMS). This column describes possible symp-toms that the machine may exhibit. Find the list-ing that best describes the symptom that themachine is exhibiting. Symptoms are groupedinto two main categories: Output Problems, andWelding Problems.
Step 2. PERFORM EXTERNAL TESTS. Thesecond column, labeled “POSSIBLE AREAS OFMISADJUSTMENT(S)”, lists the obvious externalpossibilities that may contribute to the machinesymptom. Perform these tests/checks in the orderlisted. In general, these tests can be conductedwithout removing the case wrap-around cover.
Step 3. PERFORM COMPONENT TESTS. Thelast column, labeled “Recommended Course ofAction” lists the most likely components that mayhave failed in your machine. It also specifies theappropriate test procedure to verify that the sub-ject component is either good or bad. If there area number of possible components, check thecomponents in the order listed to eliminate onepossibility at a time until you locate the cause ofyour problem.
All of the referenced test procedures referred to inthe Troubleshooting Guide are described in detailat the end of this chapter. Refer to theTroubleshooting and Repair Table of Contents tolocate each specific Test Procedure. All of thereferred to test points, components, terminalstrips, etc., can be found on the referenced elec-trical wiring diagrams and schematics. Refer tothe Electrical Diagrams Section Table ofContents to locate the appropriate diagram.
WARNING
If for any reason you do not understand the test procedures or are unable to perform the test/repairssafely, contact the Lincoln Electric Service Department for electrical troubleshooting assistance beforeyou proceed. Call1-888-935-3877.
OSCILLOSCOPE WARNING
Do not use oscilloscopes and other test equipment which are powered by 115 VAC. This equipmentshould not be used with inverter-type machines, such as Invertec STT. There are high voltages pre-sent, which are “floating” off case ground (floating ground). Connecting the ground lead of a test probe(which may be connected to the case of the test equipment) to a high voltage potential presents a shockhazard as well as the possibility of damage to the equipment in question.
WARNING
CAUTION
ELECTRIC SHOCK can kill.
Have an electrician install and servicethis equipment. Turn the machine OFFbefore working on equipment. Do nottouch electrically hot parts.
Sometimes machine failures appear to be due to PCboard failures. These problems can sometimes betraced to poor electrical connections. To avoid prob-lems when troubleshooting and replacing PC boards,please use the following procedure:
1. Determine to the best of your technical ability thatthe PC board is the most likely component causingthe failure symptom.
2. Check for loose connections at the PC board toassure that the PC board is properly connected.
3. If the problem persists, replace the suspect PCboard using standard practices to avoid static elec-trical damage and electrical shock. Read the warn-ing inside the static resistant bag and perform thefollowing procedures:
PC Board can be damaged bystatic electricity.
• Remove your body’s static chargebefore opening the static-shieldingbag. Wear an anti-static wriststrap. For safety, use a 1 Megohm resistive cord connected to agrounded part of the equipmentframe.
• If you don’t have a wrist strap,touch an unpainted, grounded,part of the equipment frame. Keeptouching the frame to prevent sta-tic build-up. Be sure not to touchany electrically live parts at thesame time.
• Tools which come in contact with the PC Board mustbe either conductive, anti-static or static-dissipative.
• Remove the PC Board from the static-shielding bagand place it directly into the equipment. Don’t set thePC Board on or near paper, plastic or cloth whichcould have a static charge. If the PC Board can’t beinstalled immediately, put it back in the static-shieldingbag.
• If the PC Board uses protective shorting jumpers,don’t remove them until installation is complete.
• If you return a PC Board to The Lincoln ElectricCompany for credit, it must be in the static-shieldingbag. This will prevent further damage and allow prop-er failure analysis.
4. Test the machine to determine if the failure symp-tom has been corrected by the replacement PCboard.
NOTE: Allow the machine to heat up so that all electri-cal components can reach their operating tem-perature.
5. Remove the replacement PC board and substituteit with the original PC board to recreate the originalproblem.
a. If the original problem does not reappearby substituting the original board, then thePC board was not the problem. Continueto look for bad connections in the controlwiring harness, junction blocks, and termi-nal strips.
b. If the original problem is recreated by thesubstitution of the original board, then thePC board was the problem. Reinstall thereplacement PC board and test themachine.
6. Always indicate that this procedure was followedwhen warranty reports are to be submitted.
NOTE: Following this procedure and writing on thewarranty report, “INSTALLED ANDSWITCHED PC BOARDS TO VERIFY PROB-LEM,” will help avoid denial of legitimate PCboard warranty claims.
TROUBLESHOOTING & REPAIRF-3 F-3
INVERTEC STTRet
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PC BOARD TROUBLESHOOTING PROCEDURES
WARNING
ATTENTIONStatic-SensitiveDevicesHandle only atStatic-SafeWorkstations
ReusableContainerDo Not Destroy
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TROUBLESHOOTING & REPAIRF-4 F-4
INVERTEC STT
Observe Safety Guidelines TROUBLESHOOTING GUIDEdetailed in the beginning of this manual.
CAUTIONIf for any reason you do not understand the test procedures or are unable to perform the test/repairs safely, con-tact the Lincoln Electric Service Department for electrical troubleshooting assistance before you proceed. Call 1-888-935-3877.
PROBLEMS(SYMPTOMS)
POSSIBLE AREAS OFMISADJUSTMENT(S)
RECOMMENDEDCOURSE OF ACTION
OUTPUT PROBLEMS
Major physical or electrical damageis evident.
1. Contact your local LincolnAuthorized Field ServiceFacility.
1. Contact the Lincoln ElectricService Department, 1-888-935-3877.
Machine has no open circuit volt-age. Wire feeds OK.
1. Check the control cablebetween the feeder and theSTT unit. Make sure the #2 and#4 leads are intact.
2. Put a jumper wire between Pins"C" and "D" on the 14 pinamphenol. If normal open cir-cuit voltage (85VDC) isrestored, the problem is in thefeeder control cable or the wirefeeder.
3. Make sure the reconnect switchS7 is in the correct position forthe three-phase input voltagebeing applied.
Do not switch reconnect switchwith input power applied tomachine.
1. Perform the T1 AuxiliaryTransformer Test.
2. Perform the T4 AuxiliaryTransformer Test.
3. Perform the Power Board Test.
4. Perform the Trigger CircuitTest.
5. Perform Capacitor BalanceTest.
6. Perform the Protection BoardTest.
7. Perform the Switch BoardTest.
8. Check for loose or broken con-nections on the heavy currentcarrying conductors (i.e., maintransformer, choke, outputdiodes, IGBT module and out-put terminals).
9. The control PC board may befaulty. Replace.
CAUTION
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TROUBLESHOOTING & REPAIRF-5 F-5
INVERTEC STT
TROUBLESHOOTING GUIDE Observe Safety Guidelinesdetailed in the beginning of this manual.
CAUTIONIf for any reason you do not understand the test procedures or are unable to perform the test/repairs safely, con-tact the Lincoln Electric Service Department for electrical troubleshooting assistance before you proceed. Call 1-888-935-3877.
PROBLEMS(SYMPTOMS)
POSSIBLE AREAS OFMISADJUSTMENT(S)
RECOMMENDEDCOURSE OF ACTION
OUTPUT PROBLEMSMachine has no welding output (noopen circuit voltage), and the wirefeeder does not feed wire when thegun trigger is pulled.
1. The 42VAC circuit breaker CB1may be tripped. Reset if neces-sary.
2. Check the 4 amp slow blow fuselocated on the reconnect panel.Replace if faulty.
3. Put a jumper between pins "A"and "C" on the 5 pin amphenollocated on the LN-742 wirefeeder. If wire feeds, check thegun trigger. Repair or replace ifnecessary.
4. Check for the presence of42VAC at pins "K" and "I" on the14 pin amphenol. If the 42VACis present and the feeder doesnot work, the problem is in thefeeder control cable or the wirefeeder.
1. If 42VAC is NOT present at pins"K" and "I" on the 14 pin amphe-nol, perform the T1 AuxiliaryTransformer Test.
2. Check leads #43 and #212C forloose or faulty connectionsbetween the T1 auxiliary trans-former and the remote protec-tion board. See the WiringDiagram. Also check the conti-nuity through the remote protec-tion board to the 14 pin amphe-nol. See the Remote ProtectionBoard Schematic.
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TROUBLESHOOTING & REPAIRF-6 F-6
INVERTEC STT
Observe Safety Guidelines TROUBLESHOOTING GUIDEdetailed in the beginning of this manual.
CAUTIONIf for any reason you do not understand the test procedures or are unable to perform the test/repairs safely, con-tact the Lincoln Electric Service Department for electrical troubleshooting assistance before you proceed. Call 1-888-935-3877.
PROBLEMS(SYMPTOMS)
POSSIBLE AREAS OFMISADJUSTMENT(S)
RECOMMENDEDCOURSE OF ACTION
OUTPUT PROBLEMS
Machine is dead - no output - nofan - no display.
1. The power switch must be in the"ON" position.
2. Check the input voltage. Makesure all three phases areapplied to the machine.
3. With input power removed,check that the input voltage set-up switch and jumper "A" (thereconnect auxiliary jumper) arein the proper position for theinput voltage being used.
4. With input power removed,check the continuity of the 4amp slow blow fuse located onthe reconnect panel.
1. The input power switch (S1)may be faulty. Check orreplace.
2. Perform the T1 AuxiliaryTransformer Test.
No output or reduced output thefirst time power is applied to themachine.
1. Check input voltages, fuses andinput voltage reconnect proce-dures. See the Installationsection.
2. If high input voltage (380VAC orhigher) is applied, the capaci-tors may need conditioning. Letthe "unloaded" machine idle for30 minutes.
1. Contact the Lincoln ElectricService Department. 1-888-935-3877.
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TROUBLESHOOTING & REPAIRF-7 F-7
INVERTEC STT
TROUBLESHOOTING GUIDE Observe Safety Guidelinesdetailed in the beginning of this manual.
CAUTIONIf for any reason you do not understand the test procedures or are unable to perform the test/repairs safely, con-tact the Lincoln Electric Service Department for electrical troubleshooting assistance before you proceed. Call 1-888-935-3877.
PROBLEMS(SYMPTOMS)
POSSIBLE AREAS OFMISADJUSTMENT(S)
RECOMMENDEDCOURSE OF ACTION
OUTPUT PROBLEMS
No output. Main fuses are open,indicating excessive current draw.
1. With the input power removed,inspect input leads for possibleshorts or grounds or miscon-nections.
2. Install new fuses and reapplypower. If fuses open again,contact your local LincolnAuthorized Field ServiceFacility.
1. Check the input power switch(S1) and the reconnect switchfor "shorted" or "grounded"wires or connections.
2. Perform the Input RectifierTest.
3. Perform the Switch BoardTest.
Machine loses output when guntrigger is pulled or arc is struck.Machine output returns after a fewseconds and trigger is pulled again.The thermal indicator light is lit.
1. The overcurrent sensor is acti-vated, indicating that too muchoutput current is being drawnfrom the machine. Reducewelding current demands orremove the "fault" in weldingcables.
2. Make sure that the gun tip is not"shorted" to the work surfaceand that the proper welding pro-cedures are being used.
1. The current sensor may befaulty.
2. The control PC board may befaulty.
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F-8 F-8
INVERTEC STT
TROUBLESHOOTING & REPAIR
TROUBLESHOOTING GUIDE Observe Safety Guidelinesdetailed in the beginning of this manual.
CAUTIONIf for any reason you do not understand the test procedures or are unable to perform the test/repairs safely, con-tact the Lincoln Electric Service Department for electrical troubleshooting assistance before you proceed. Call 1-888-935-3877.
PROBLEMS(SYMPTOMS)
POSSIBLE AREAS OFMISADJUSTMENT(S)
RECOMMENDEDCOURSE OF ACTION
OUTPUT PROBLEMS
Machine loses output while weld-ing. The thermal indicator light islit. Normal welding output returnsafter about 10 minutes.
1. Check to make sure the fan isrunning and operating correctly.
2. Welding application mayexceed recommended dutycycle.
3. Dirt and dust may have cloggedthe cooling channels. Blow outthe unit with clean, dry com-pressed air.
4. Air intake and exhaust louversmay be blocked due to inade-quate clearance around themachine.
1. The IGBT heat sink thermostator fan thermostat may be defec-tive. Check or replace.
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TROUBLESHOOTING & REPAIRF-9 F-9
INVERTEC STT
Observe Safety Guidelines TROUBLESHOOTING GUIDEdetailed in the beginning of this manual.
CAUTIONIf for any reason you do not understand the test procedures or are unable to perform the test/repairs safely, con-tact the Lincoln Electric Service Department for electrical troubleshooting assistance before you proceed. Call 1-888-935-3877.
PROBLEMS(SYMPTOMS)
POSSIBLE AREAS OFMISADJUSTMENT(S)
RECOMMENDEDCOURSE OF ACTION
WELDING PROBLEMS
Porosity in the weld. 1. Make sure the gas type andflow rate is correct for the pro-cedure being used. Shield thework from excessive outside aircurrents.
2. Check the gun and nozzle forleaks or obstructions.
3. Make certain the machine andwire feed settings are correct forthe process.
1. Contact the Lincoln ElectricService Department. 1-888-935-3877.
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TROUBLESHOOTING & REPAIRF-10 F-10
INVERTEC STT
TROUBLESHOOTING GUIDE Observe Safety Guidelinesdetailed in the beginning of this manual.
CAUTIONIf for any reason you do not understand the test procedures or are unable to perform the test/repairs safely, con-tact the Lincoln Electric Service Department for electrical troubleshooting assistance before you proceed. Call 1-888-935-3877.
PROBLEMS(SYMPTOMS)
POSSIBLE AREAS OFMISADJUSTMENT(S)
RECOMMENDEDCOURSE OF ACTION
WELDING PROBLEMS
Weld bead appears "cold." 1. One or more of the machinesettings may be wrong. Checkthe Background, Peak Current,Tailout (STT II Only), and WireSpeed controls for proper set-tings. Adjust for optimum weld-ing performance.
2. Make sure the Wire Type andWire Size switches are in thecorrect position for the elec-trode wire being used.
1. Check for the correct open cir-cuit voltage (approximately85VDC). If the correct open cir-cuit voltage IS present, theBackground control (R12) orthe Peak Current (R11) andassociated wiring may be faulty.See the Wiring Diagram. Thecontrol PC board may be faulty.Also check for loose or faultyconnections on the heavy cur-rent carrying conductors (i.e.,main transformer, choke, outputdiodes, IGBT module and out-put terminals).
2. If the correct open circuit volt-age is NOT present, performthe Switch Board Test.
3. The output diodes may befaulty. Check or replace if nec-essary.
4. The driver PC board and orcontrol PC board may be faulty.
5. The IGBT module may befaulty. Check or replace.
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TROUBLESHOOTING & REPAIRF-11 F-11
INVERTEC STT
Observe Safety Guidelines TROUBLESHOOTING GUIDEdetailed in the beginning of this manual.
CAUTIONIf for any reason you do not understand the test procedures or are unable to perform the test/repairs safely, con-tact the Lincoln Electric Service Department for electrical troubleshooting assistance before you proceed. Call 1-888-935-3877.
PROBLEMS(SYMPTOMS)
POSSIBLE AREAS OFMISADJUSTMENT(S)
RECOMMENDEDCOURSE OF ACTION
WELDING PROBLEMS
Molten weld puddle appears exces-sively "violent."
1. The Wire Type switch may be inthe wrong position for the elec-trode wire being used.
2. The Peak Current or Back-ground Setting may be too high.Adjust for optimum welding per-formance.
3. The Tailout may not be set cor-rectly for the process. (STT IIOnly)
1. The IGBT module may be faulty.Check or replace.
2. The IGBT driver PC board maybe faulty.
3. The control PC board may befaulty.
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TROUBLESHOOTING & REPAIRF-12 F-12
INVERTEC STT
TROUBLESHOOTING GUIDE Observe Safety Guidelinesdetailed in the beginning of this manual.
CAUTIONIf for any reason you do not understand the test procedures or are unable to perform the test/repairs safely, con-tact the Lincoln Electric Service Department for electrical troubleshooting assistance before you proceed. Call 1-888-935-3877.
PROBLEMS(SYMPTOMS)
POSSIBLE AREAS OFMISADJUSTMENT(S)
RECOMMENDEDCOURSE OF ACTION
WELDING PROBLEMS
Excessive weld spatter. Arcsounds and looks like a standardMIG process.
1. Check the Arc Sense leads forloose or faulty connections.
2. Make sure the Arc Sense"WORK" lead is as close aspossible to the welding arc.
3. Make sure the machine andwire feed settings are correct forthe process and wire beingused.
1. The IGBT module may be faulty.Check or replace.
2. The IGBT driver PC board maybe faulty.
3. The control PC board may befaulty.
Poor welding, weld settings drift, oroutput power is low.
1. Make sure the machine settingsare correct for the weldingprocess being used.
2. Check the welding cables forloose or faulty connections.
3. Make sure the reconnect switchS7 is in the correct position forthe three-phase input voltagebeing applied.
Do not switch reconnect switch withinput power applied to machine.
1. The current sensor may befaulty. Check associated leadsfor loose or faulty connections.
2. The control PC board may befaulty.
CAUTION
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TROUBLESHOOTING & REPAIRF-13 F-13
INVERTEC STT
T1 AUXILIARY TRANSFORMER TEST
WARNING
Service and repair should be performed by only Lincoln Electric factory trained personnel.Unauthorized repairs performed on this equipment may result in danger to the technicianor machine operator and will invalidate your factory warranty. For your safety and to avoidelectrical shock, please observe all safety notes and precautions detailed throughout thismanual.
If for any reason you do not understand the test procedures or are unable to perform thetest/repairs safely, contact the Lincoln Electric Service Department for electrical trou-bleshooting assistance before you proceed. Call 1-888-935-3877
TEST DESCRIPTION
This test will determine if the correct voltages are being:
a. applied to the primary of the T1 auxiliary transformer.
b. induced upon the secondary windings of the T1 auxiliary transformer.
MATERIALS NEEDED
Volt/Ohmmeter (Multimeter)Invertec STT wiring diagrams5/16" Nut driver3/8" WrenchSlot head screw driver
Note: Component locations and disassembly procedures mayvary slightly on STT II models
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TROUBLESHOOTING & REPAIRF-14 F-14
INVERTEC STT
T1 AUXILIARYTRANSFORMER
PLUGJ31
PLUGJ30
FIGURE F.1 – T1 AUXILIARY TRANSFORMER AND J30/J31 LOCATION
T1 AUXILIARY TRANSFORMER TEST (continued)
TEST PROCEDURE
1. Turn off Invertec STT and disconnect mainAC input power to the machine.
2. Using the 5/16" nut driver, remove the casewraparound cover.
3. Perform the Input Filter CapacitorDischarge Procedure. See theMaintenance section.
ELECTRIC SHOCK can kill.
• Before continuing withthe test procedure, per-form the capacitor dis-charge procedure toavoid electric shock.
4. Locate the T1 auxiliary transformer and sec-ondary lead molex plugs (J30 and J31) onthe left side, just in front of the main trans-former assembly. Check for broken or loosewires. See Figure F.1.
WARNING
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TROUBLESHOOTING & REPAIRF-15 F-15
INVERTEC STT
5. Locate the primary lead molex plug (J21)just behind the reconnect panel assembly onthe right side of the machine. Check for bro-ken or loose wires. See Figure F.2.
6. Disconnect plugs J30 and J31 from thewiring harness.
ELECTRIC SHOCK can kill.
• With input power ON,there are high voltagesinside the machine. Donot reach into themachine or touch anyinternal part.
7. Apply the correct input power to the machineand test for the correct secondary voltagesat plugs J30 and J31. (Make sure the recon-nect panel is configured properly for theinput voltage being applied.) See Table F.1.
T1 AUXILIARY TRANSFORMER TEST (continued)
RECONNECTPANEL
PLUG J21LOCATION BEHIND
RECONNECT PANEL
FIGURE F.2 – PRIMARY LEAD PLUG J21 LOCATION
WARNING
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TROUBLESHOOTING & REPAIRF-16 F-16
INVERTEC STT
8. If the correct secondary voltages are present(according to Table F.1), the T1 transformeris functioning properly.
9. If the secondary voltages are missing orincorrect, the primary voltages must bechecked.
10. Remove input power to the STT machine.
11. Perform the Input Filter CapacitorDischarge Procedure.
12. Reconnect Plugs J30 & J31.
ELECTRIC SHOCK can kill.
• Before continuing withthe test procedure, per-form the capacitor dis-charge procedure toavoid electric shock.
13. Gain access to the primary lead plug J21 byremoving the reconnect panel assemblyfrom the upper support panel using the 3/8"wrench and slot head screwdriver. This willallow the reconnect panel assembly to bemoved out of the way. Be careful NOT tostress the leads connected to the reconnectpanel. See Figure F.2.
14. Before applying input power make certainthe reconnect panel assembly is insulatedand supported for safe operation.
T1 AUXILIARY TRANSFORMER TEST (continued)
TABLE F.1 – T1 AUXILIARY TRANSFORMER VOLTAGES
TEST POINTS
PLUG J30 PINS 1 TO 2 (LEADS 32 TO 33)
PLUG J31 PINS 1 TO 4 (LEADS 501 TO 504)
PLUG J31 PINS 2 TO 3(LEADS 212 TO 503)
PLUG J31 PINS 2 TO 5(LEADS 212 TO 43A)
PLUG J21 PINS 1 TO 4(LEADS H1 TO H2)
PLUG J21 PINS 1 TO 2(LEADS H1 TO H3)
PLUG J21 PINS 1 TO 3(LEADS H1 TO H4)
PLUG J21 PINS 1 TO 6(LEADS H1 TO H5) (H6)
NORMAL VOLTAGE
115VAC
18VAC
24VAC
42VAC
200/208VAC
220/230VAC
380/415VAC
440/460VAC
WARNING
NOTE: If the main AC input supply voltage varies, the auxiliary transformer voltages will vary bythe same percentages.
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TROUBLESHOOTING & REPAIRF-17 F-17
INVERTEC STT
ELECTRIC SHOCK can kill.
• With input power ON,there are high voltagesinside the machine. Donot reach into themachine or touch anyinternal part.
15. Apply the correct input power and carefullytest for the correct primary voltages at plugJ21. See Table F.1.
16. If the correct AC input voltages are appliedto the primary windings and any or all of thesecondary voltages are missing or not cor-rect, the T1 auxiliary transformer may befaulty.
17. After all tests are complete, reconnect plugsJ30 and J31.
18. Install the case wraparound cover.
T1 AUXILIARY TRANSFORMER TEST (continued)
WARNING
NOTESF-18 F-18
INVERTEC STTRet
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T4 AUXILIARY TRANSFORMER TEST
Service and repair should be performed by only Lincoln Electric factory trained personnel.Unauthorized repairs performed on this equipment may result in danger to the technician ormachine operator and will invalidate your factory warranty. For your safety and to avoid elec-trical shock, please observe all safety notes and precautions detailed throughout this manual.
If for any reason you do not understand the test procedures or are unable to perform thetest/repairs safely, contact the Lincoln Electric Service Department for electrical troubleshoot-ing assistance before you proceed. Call 1-888-935-3877.
TEST DESCRIPTION
This test will determine if the correct voltages are being:
a. applied to the primary of the T4 auxiliary transformer.b. induced on the secondary windings of the T4 auxiliary transformer.
MATERIALS NEEDED
Volt/Ohmmeter (Multimeter)Invertec STT Wiring DiagramsIsolated 115VAC supply5/16" Nut driver7/16" Wrench
TROUBLESHOOTING & REPAIRF-19 F-19
INVERTEC STT
WARNING
Note: Component locations and disassembly procedures mayvary slightly on STT II models
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TROUBLESHOOTING & REPAIRF-20 F-20
INVERTEC STT
T4 AUXILIARY TRANSFORMER TEST (continued)
FIGURE F.3 – OUTPUT CHOKE/IGBT MODULE SPLICED CONNECTION
LOWERTRAYAREA
OUTPUT CHOKE/DARLINGTON MODULESPLICED CONNECTION
TEST PROCEDURE
1. Turn off the Invertec STT and disconnectmain AC input power to the machine.
2. Using the 5/16" nut driver, remove the casewraparound cover.
3. Perform the Input Filter CapacitorDischarge Procedure. See theMaintenance section.
ELECTRIC SHOCK can kill.
• Before continuing withthe test procedure, per-form the capacitor dis-charge procedure toavoid electric shock.
4. Locate the lead connection splice from theoutput choke to the IGBT module. Removethe insulating sleeve. Cut any necessarycable ties. Using the 7/16" wrench, discon-nect the lead splice. Thread the lower leaddown into the lower tray assembly area.See Figure F.3.
WARNING
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TROUBLESHOOTING & REPAIRF-21 F-21
INVERTEC STT
T4 AUXILIARY TRANSFORMER TEST (continued)
5. Disconnect the current sensing Plug J1 fromthe control PC board. Carefully remove PlugJ1 and associated leads from control boardcompartment. See Figure F.4.
FIGURE F.4 – PLUG J1 LOCATION
LOWERTRAYAREA
OUTPUT CHOKE/DARLINGTON MODULESPLICED CONNECTION
J1 CURRENTSENSING PLUG
6. Locate and disconnect plug J22 from thewiring harness. See Figure F.5.
FIGURE F.5 – PLUG J22 LOCATION
PLUG J22
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TROUBLESHOOTING & REPAIRF-22 F-22
INVERTEC STT
T4 AUXILIARY TRANSFORMER TEST (continued)
7. Carefully lift and tilt the Invertec STTmachine onto its right side. See Figure F.6.
8. Using the 7/16" wrench, remove the fivebolts holding the lower tray assembly to thecase bottom.
9. Carefully slide out and support the lower trayassembly for testing purposes.
10. Locate and remove plug J13 from theIGBT drive board. See Figure F.7.
FIGURE F.6 – STT ON ITS RIGHT SIDE
MOUNTINGBOLTS (5)
FIGURE F.7 – PLUG J13 LOCATION
T4 AUXILIARYTRANSFORMER
PLUG J13
IGBTDRIVE BOARD
STT II
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TROUBLESHOOTING & REPAIRF-23 F-23
INVERTEC STT
T4 AUXILIARY TRANSFORMER TEST (continued)
11. Locate and remove leads #32A, #32B and#33A, #33B from the T4 transformer tabs.See Figure F.8.
ELECTRIC SHOCK can kill.
• With input power ON,there are high voltagesinside the machine. Donot reach into themachine or touch anyinternal part.
12. Carefully apply the 115VAC isolated supplyto the T4 transformer at the #32 and #33tabs.
FIGURE F.8 – T4 TRANSFORMER LEAD CONNECTIONS
LEADS32A, 32B, 33A, 33B
T4 AUXILIARYTRANSFORMER
STT STT II
T4 AUXILIARYTRANSFORMER
LEADS32A, 32B, 33A, 33B
WARNING
13. Check the secondary AC voltages accord-ing to Table F.2.
14. With the correct 115VAC applied to the pri-mary winding (#32 to #33), if any or all ofthe secondary voltages are missing or low,the T4 auxiliary transformer may be faulty.Replace the T4 auxiliary transformer.
15. After all tests are completed, reconnect thefollowing:
Leads #32A, #32B, #33A, #33B to theT4 transformer tabs
Plug J13 to the IGBT drive board
Plug J22 to the wiring harness
Reinstall lower tray assembly using7/16” wrench and 5 bolts
Plug J1 to the control PC board
Reconnect lead splice from the outputchoke to the IGBT module. Repositioninsulating sleeve.
16. Install the case wraparound cover.
TROUBLESHOOTING & REPAIRF-24 F-24
INVERTEC STTRet
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TABLE F.2 – T4 AUXILIARY TRANSFORMER VOLTAGES
TEST POINTS
PLUG J13 PINS 5 TO 6
PLUG J13 PINS 2 TO 3
PLUG J22 PINS 1 TO 2(LEADS 240 TO 241)
PLUG J22 PINS 2 TO 9(LEADS 241 TO 242)
PLUG J22 PINS 3 TO 4(LEADS 243 TO 244)
PLUG J22 PINS 12 TO 13(LEADS 245 TO 246)
NORMAL VOLTAGES
6VAC
10VAC
18VAC
18VAC
18VAC
18VAC
T4 AUXILIARY TRANSFORMER TEST (continued)
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OC INPUT RECTIFIER TEST
Service and repair should be performed by only Lincoln Electric factory trained personnel.Unauthorized repairs performed on this equipment may result in danger to the technician ormachine operator and will invalidate your factory warranty. For your safety and to avoid elec-trical shock, please observe all safety notes and precautions detailed throughout this manual.
If for any reason you do not understand the test procedures or are unable to perform thetest/repairs safely, contact the Lincoln Electric Service Department for electrical troubleshoot-ing assistance before you proceed. Call 1-888-935-3877.
TEST DESCRIPTION
This test will help determine if the input rectifier and associated components are functioningproperly.
MATERIALS NEEDED
5/16" Nut driverAnalog Voltmeter/ohmmeter (Multimeter)Inverter STT Wiring Diagrams
TROUBLESHOOTING & REPAIRF-25 F-25
INVERTEC STT
WARNING
Note: Component locations and disassembly procedures mayvary slightly on STT II models
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TROUBLESHOOTING & REPAIRF-26 F-26
INVERTEC STT
INPUT RECTIFIER TEST (continued)
FIGURE F.9 - INPUT RECTIFIER LOCATION
INPUTRECTIFIERCA
9 12
B
TEST PROCEDURE
1. Turn off the Invertec STT and disconnectmain AC input power to the machine.
2. Using the 5/16" nut driver, remove the casewraparound cover.
3. Perform the Input Filter CapacitorDischarge procedure. See theMaintenance section.
ELECTRIC SHOCK can kill.
• Before continuing withthe test procedure, per-form the capacitor dis-charge procedure toavoid electric shock.
4. Locate the input rectifier. See Figure F.9.
5. Locate the leads needed to perform thetests. See Figure F.9.
6. Use an ANALOG ohmmeter to perform thetests shown in Table F.3.
WARNING
6. Replace the input rectifier when any of thetests are NOT OK.
NOTE: When installing a new input rectifier,torque the mounting nuts (in a cross-tighteningpattern) to 6 inch-pounds (.7 Nm). Torque ter-minals to 26 inch-pounds (3 Nm). PROCEEDTO STEP 7 TO CHECK RELATED COMPO-NENTS.
7. Inspect main power switch S1 and replaceif faulty. Go to step 8.
8. Test capacitors C1 and C2 and replace bothcapacitors if either is faulty.
NOTE: Faulty capacitors could be the reasonfor input rectifier failure.
Visually inspect the capacitors for leakage,damage, etc., and use appropriate test equip-ment to determine component integrity.
9. Perform the Switch Board Test.
10. After all tests are completed, install thecase wraparound cover.
TROUBLESHOOTING & REPAIRF-27 F-27
INVERTEC STTRet
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TABLE F.3 – INPUT RECTIFIER TEST
TEST POINTS
+PROBE -PROBE ACCEPTABLE METER READING
9 A Greater than 100K ohms9 B Greater than 100K ohms9 C Greater than 100K ohms
A 9 Less than 100 ohmsB 9 Less than 100 ohmsC 9 Less than 100 ohms
12 A Less than 100 ohms12 B Less than 100 ohms12 C Less than 100 ohms
A 12 Greater than 100K ohmsB 12 Greater than 100K ohmsC 12 Greater than 100K ohms
NOTESF-28 F-28
INVERTEC STTRet
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Service and repair should be performed by only Lincoln Electric factory trained personnel.Unauthorized repairs performed on this equipment may result in danger to the technician ormachine operator and will invalidate your factory warranty. For your safety and to avoid elec-trical shock, please observe all safety notes and precautions detailed throughout this manual.
If for any reason you do not understand the test procedures or are unable to perform thetest/repairs safely, contact the Lincoln Electric Service Department for electrical troubleshoot-ing assistance before you proceed. Call 1-888-935-3877.
TEST DESCRIPTION
This test will help determine if the capacitors, bleeder resistors and switch boards are func-tioning properly.
MATERIALS NEEDED
5/16" Nut driverAnalog Volt/ohmmeter (Multimeter)
TROUBLESHOOTING & REPAIRF-29 F-29
INVERTEC STT
WARNING
Note: Component locations and disassembly procedures mayvary slightly on STT II models
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TROUBLESHOOTING & REPAIRF-30 F-30
INVERTEC STT
CAPACITOR BALANCE TEST (continued)
FIGURE F.10 – SWITCH BOARD TEST POINTS
L8441L8441 SWITCHSWITCH
99 1212
TEST PROCEDURE
1. Turn off the Invertec STT and disconnectmain AC input power to the machine.
2. Using the 5/16" nut driver, remove thecase wraparound cover.
ELECTRIC SHOCK can kill.
• With input power ON,there are high voltagesinside the machine. Donot reach into themachine or touch anyinternal part.
3. Carefully apply the correct input power tothe machine.
NOTE: This test should only be conductedwhen the machine reconnect switch andjumper are set for high voltage (above380VAC) and the proper line voltage is applied.
4. Test for VDC across terminals #9 and #12 ofone switch board and repeat the test for theother switch board. See Table F.4 in thisprocedure for expected voltage readings.See Figure F.10.
A. If less than 25VDC difference is mea-sured between each switch board, thecapacitive balance is OK. This indi-cates that capacitors C1, C2, and resis-tors R1 and R9 are functioning proper-ly. Proceed to Step #5.
B. If more than 25VDC difference is mea-sured between each switch board, testeach of the following components:Capacitors C1, C2 and resistors R1and R9. See the Invertec STT WiringDiagram.
WARNING
5. Adjust the Peak and Background controls tothe minimum settings (controls on casefront).
6. Jumper together pins "C" and "D" on the 14pin amphenol. This will energize the outputterminals.
7. Test for VDC across terminals #9 and #12 ofone switch board and repeat the test for theother switch board. See Table F.4 in thisprocedure for expected voltage readings.See Figure F.10.
A. If less than 15VDC difference is mea-sured between each switch board, thetest is OK.
B. If more than 15VDC difference is mea-sured between each switch board, theswitch board(s) and or power PC boardmay be faulty. Perform the SwitchBoard Test. Perform the Power BoardTest.
8. After all tests are completed, remove thejumper between pins C and D on the 14-pinamphenol.
9. Install the case wraparound cover.
TROUBLESHOOTING & REPAIRF-31 F-31
INVERTEC STTRet
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CAPACITOR BALANCE TEST (continued)
TABLE F.4 – EXPECTED VOLTAGE READINGS
If VAC Input is:
460 VAC440 VAC415 VAC380 VAC
VDC at terminals #9 (+) and #12 (-)should be approximately:
325VDC311VDC293VDC269VDC
NOTESF-32 F-32
INVERTEC STTRet
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OC SWITCH BOARD TEST
Service and repair should be performed by only Lincoln Electric factory trained personnel.Unauthorized repairs performed on this equipment may result in danger to the technician ormachine operator and will invalidate your factory warranty. For your safety and to avoid elec-trical shock, please observe all safety notes and precautions detailed throughout this manual.
If for any reason you do not understand the test procedures or are unable to perform thetest/repairs safely, contact the Lincoln Electric Service Department for electrical troubleshoot-ing assistance before you proceed. Call 1-888-935-3877.
TEST DESCRIPTION
The Switch Board Test determines if the switch boards are operating properly. This resistancetest is preferable to a voltage test with the machine energized because these boards can bedamaged easily. In addition, it is dangerous to work on these boards with machine power ON.
MATERIALS NEEDED
Analog Volt/ohmmeter (Multimeter)5/16" Nut driver
TROUBLESHOOTING & REPAIRF-33 F-33
INVERTEC STT
WARNING
Note: Component locations and disassembly procedures mayvary slightly on STT II models
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TROUBLESHOOTING & REPAIRF-34 F-34
INVERTEC STT
SWITCH BOARD TEST (continued)
FIGURE F.11 - SWITCH BOARD RESISTANCE TEST
TEST PROCEDURE
NOTE: There are two switch boards. One islocated on each side of the machine.
NOTE: The switch boards are designed toreceive gate (turn-on) signals from the driverboard (pulse transformer secondaries). Theinternal board circuitry processes the signals andoutputs them to the FETs. The switch board cir-cuitry contains snubber circuitry to protect theFETs. This protection is supplemented by off-board resistors. The switch board design accom-modates the connection point(s) for the capaci-tor(s), main transformer primary windings, inputrectifier, and reconnect switches.
1. Turn off Invertec STT and disconnect mainAC input power to the machine.
2. Using the 5/16" nut driver, remove the casewraparound cover.
3. Perform the Input Filter CapacitorDischarge Procedure. See theMaintenance section.
ELECTRIC SHOCK can kill.
• Before continuing with thetest procedure, performthe capacitor dischargeprocedure to avoid electricshock.
4. Disconnect all wiring harness leads(401/403, 1/8, 9, 12, 4/5, 402/404) from theswitch board.
5. Fold the leads up so they do not interfere withthe exposed terminals. See Figure F.11.
6. Using an analog ohmmeter, perform the resis-tance tests detailed in Table F.5 and shown inFigure F.11. If any test fails, replace bothswitch boards. See the Switch BoardRemoval and Replacement procedure.
7. If the switch boards appear to be burned oroverheated, or if the machine was supplied bya 380 VAC or higher voltage supply when thefailure occurred, replace the capacitors andthe switch boards.
WARNING
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TROUBLESHOOTING & REPAIRF-35 F-35
INVERTEC STT
SWITCH BOARD TEST (continued)
Apply Positive Apply NegativeTest Probe to Test Probe toTerminal Terminal Test Result Conclusion Repair Action Next Procedure Notes
1/8 12 Greater than OK None Continue1K ohm
Less than Shorted Replace both Snubber Test100 ohms switch boards
12 1/8 Less than OK None Continue100 ohms
Greater than Open Replace both Snubber Test1K ohm switch boards
9 4/5 Greater than OK None Continue1K ohm
Less than Shorted Replace both Snubber Test100 ohms switch boards
4/5 9 Less than OK None Continue100 ohms
Greater than Open Replace both Snubber Test1K ohm switch boards
1/8 9 Less than OK None Continue100 ohms
Greater than Open Replace both Snubber Test1K ohm switch boards
9 1/8 Greater than OK None Continue1K ohm
Less than Shorted Replace both Snubber Test100 ohms switch boards
12 4/5 Less than OK None Continue100 ohms
Greater than Open Replace both Snubber Test1K ohm switch boards
4/5 12 Greater than OK None Continue1K ohm
Less than Shorted Replace both Snubber Test100 ohms switch boards
Continued . . .
NOTE: K ohm = ohm reading multiplied by 1000.NOTE: Always make sure that switch boards are changed in matched pairs. Never mix an old style (different
part number) switch board with a new switch board (new part number).
TABLE F.5 – SWITCH BOARD RESISTANCE TEST
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TROUBLESHOOTING & REPAIRF-36 F-36
INVERTEC STT
Apply Positive Apply NegativeTest Probe to Test Probe toTerminal Terminal Test Result Conclusion Repair Action Next Procedure Notes
12 401/403 Greater than OK None Continue1K ohm
Less than Shorted Replace both Snubber Test100 ohms switch boards
401/403 12 Less than OK None Continue100 ohms
Greater than Open Replace both Snubber Test1K ohm switch boards
9 402/404 Less than OK None Continue100 ohms
Greater than Open Replace both Snubber Test1K ohm switch boards
402/404 9 Greater than OK None Continue1K ohm
Less than Shorted Replace both Snubber Test100 ohms switch boards
SWITCH BOARD TEST (continued)
NOTE: K ohm = ohm reading multiplied by 1000.NOTE: Always make sure that switch boards are changed in matched pairs. Never mix an old style (different
part number) switch board with a new switch board (new part number).
TABLE F.5 – SWITCH BOARD RESISTANCE TEST (continued)
8. Reconnect all wiring harness leads (401/403,1/8, 9, 12, 4/5, 402/404) to the switch board.
9. Install the case wraparound cover.
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SNUBBER RESISTORS TEST
Service and repair should be performed by only Lincoln Electric factory trained personnel.Unauthorized repairs performed on this equipment may result in danger to the technician ormachine operator and will invalidate your factory warranty. For your safety and to avoid elec-trical shock, please observe all safety notes and precautions detailed throughout this manual.
If for any reason you do not understand the test procedures or are unable to perform thetest/repairs safely, contact the Lincoln Electric Service Department for electrical troubleshoot-ing assistance before you proceed. Call 1-888-935-3877.
DESCRIPTION
This test will determine if the snubber resistors (R4, R5, R6, R7) are functioning properly.
MATERIALS NEEDED
Analog Volt/ohmmeter (Multimeter)STT Wiring Diagrams5/16” Nut driver
TROUBLESHOOTING & REPAIRF-37 F-37
INVERTEC STT
WARNING
Note: Component locations and disassembly procedures mayvary slightly on STT II models
TROUBLESHOOTING & REPAIRF-38 F-38
INVERTEC STTRet
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SNUBBER RESISTORS TEST (continued)
FIGURE F.12 - REMOVING LEADS
TEST PROCEDURE
1. Turn off Invertec STT and disconnect mainAC input power to the machine.
2. Using the 5/16" nut driver, remove the casewraparound cover.
3. Perform the Input Filter CapacitorDischarge Procedure. See theMaintenance section.
ELECTRIC SHOCK can kill.
• Before continuing with thetest procedure, performthe capacitor dischargeprocedure to avoid electricshock.
4. Locate and gain access to the switch board.
5. Remove leads from terminals 401/403,402/404 on the switch board. See FigureF.12.
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TROUBLESHOOTING & REPAIRF-39 F-39
INVERTEC STT
SNUBBER RESISTORS TEST (continued)
FIGURE F.13 - SWITCH BOARD TEST POINTS
6. Test for 25 ohms resistance from lead termi-nal 401 to terminal 12 on the switch board.See Figure F.13.
a. If 25 ohms is measured, resistor R4 is OK.
b. If 30 ohms or more is measured, resistorR4 is faulty and must be replaced.
c. If 20 ohms or less is measured, resistorR4 is faulty and must be replaced.
7. Repeat the same procedures to test R5, R6,and R7 according to Table F.6.
8. Reconnect leads 401/403 and 402/404 to theswitch board.
9. Install the case wraparound cover.
L8441 L8441 SWITCHSWITCH
401401/403 12129 12402/404
Check Test Result Conclusion Next Test Step Repair Action
Lead 401 to 25 ohms OK ContinueTerminal 12 >30 ohms R4 open Replace R4
<20 ohms R4 faulty
Lead 402 to 25 ohms OK ContinueTerminal 9 >30 ohms R5 open Replace R5
<20 ohms R5 faulty
Lead 403 to 25 ohms OK ContinueTerminal 12 >30 ohms R6 open Replace R6
<20 ohms R6 faulty
Lead 404 to 25 ohms OK ContinueTerminal 9 >30 ohms R7 open Replace R7
<20 ohms R7 faulty
> = GREATER THAN < = LESS THAN
TABLE F.6 – SNUBBER RESISTORS TEST
NOTESF-40 F-40
INVERTEC STTRet
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OC POWER BOARD TEST
Service and repair should be performed by only Lincoln Electric factory trained personnel.Unauthorized repairs performed on this equipment may result in danger to the technician ormachine operator and will invalidate your factory warranty. For your safety and to avoid elec-trical shock, please observe all safety notes and precautions detailed throughout this manual.
If for any reason you do not understand the test procedures or are unable to perform thetest/repairs safely, contact the Lincoln Electric Service Department for electrical troubleshoot-ing assistance before you proceed. Call 1-888-935-3877.
TEST DESCRIPTION
This test will help determine if the power PC board is receiving the correct AC voltages andalso if the correct DC voltages are being generated on the power PC board.
MATERIALS NEEDED
5/16" Nut driverVolt/ohmmeter (Multimeter)Wiring diagram
TROUBLESHOOTING & REPAIRF-41 F-41
INVERTEC STT
WARNING
Note: Component locations and disassembly procedures mayvary slightly on STT II models
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TROUBLESHOOTING & REPAIRF-42 F-42
INVERTEC STT
POWER BOARD TEST (continued)
FIGURE F.14 – REMOVING THE FRONT PANEL ASSEMBLY
POWERPC BOARD(Locatedon Back ofCase Front)
QUICK CHECK PROCEDURE
1. Turn off the Invertec STT and disconnectmain AC input power to the machine.
2. Using the 5/16" nut driver, remove the casewraparound cover.
3. Locate relays CR1 and CR2 just to the front ofthe fan motor.
ELECTRIC SHOCK can kill.
• With input power ON,there are high voltagesinside the machine. Donot reach into the machineor touch any internal part.
4. Apply the correct input power and turn ON theInvertec STT machine.
5. After about a 5 second delay the relaysshould activate. This can be determined byan audible click which can be heard when therelays are activated. If the relays are beingactivated, the power PC board is most likely
OK. If the relays are NOT being activated, thepower PC board could be faulty. Continuewith the voltage tests.
VOLTAGE TEST PROCEDURE
1. Remove input power to the Invertec STT.
2. Perform the Input Filter Capacitor DischargeProcedure. See the Maintenance section.
ELECTRIC SHOCK can kill.
• Before continuing with thetest procedure, performthe capacitor dischargeprocedure to avoid electricshock.
3. Using the 5/16" nut driver, loosen the frontcontrol panel by removing the four sheetmetal screws from the top and bottom of thefront panel. Carefully move the front panelassembly to the right to gain access to thepower PC board. See Figure F.14.
WARNINGWARNING
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TROUBLESHOOTING & REPAIRF-43 F-43
INVERTEC STT
POWER BOARD TEST (continued)
FIGURE F.15 – POWER PC BOARD TEST POINTS
POWER BOARD
J6J7 J14
L8033
501
504
302
275
211A 305
311313
309 310 301212A
4. Secure and insulate the front panel assemblyfor POWER ON testing.
ELECTRIC SHOCK can kill.
• With input power ON,there are high voltagesinside the machine. Donot reach into the machineor touch any internal part.
5. Apply the correct input power and turn ON themachine.
6. Carefully test for 18VAC input from the T1Auxiliary Transformer between plug J7 pin 5(lead#501) and plug J7 pin 6 (lead #504) atthe power PC board. See Figure F. 15.
NOTE: If the 18VAC is NOT present, performthe T1 Auxiliary Transformer Test. Also checkassociated wiring. See the Wiring Diagram.
WARNING
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TROUBLESHOOTING & REPAIRF-44 F-44
INVERTEC STT
POWER BOARD TEST (continued)FIGURE F.16 – SIMPLIFIED TRIGGER CIRCUIT
FROM PROTECTIONBOARD OVERVOLTAGE
PWM OUTPUTS
TO POWERBOARD
7J6
2J6
11J4
3J4
13J36
5J36
8J33
6J34
9J4
12J4
3J31 6J22 6J4
POWER BOARD CONTROL BOARD
REMOTE PROTECTION
BOARD
14 AMPHENOL
#301
#305
#503A
#224 #210
#212
#223
#212C
#413
#405
C
D
T1 AUXILIARYTRANSFORMER
24VAC
PWM
5J4TOPOWERBOARD
2J31
3.5 ohms
3.5 ohms
STT II Only
#379
7. Carefully test for 15VDC output from thepower PC board at plug J6 pin1 (lead #275) (-) and plug J6 pin 6 (lead #302)(+). SeeFigure F.15.
NOTE: If the 18VAC is present but the 15VDC isNOT, the power PC board may be faulty.
8. Carefully test for 24VAC input from the T1Auxiliary Transformer between plug J6 pin 4(lead#211A) and plug J6 pin 9 (lead#212A).See Figure F.15.
NOTE: If the 24VAC is NOT present, perform theT1 Auxiliary Transformer Test. Also check theassociated wiring. See the Wiring Diagram. Thecontrol PC board or thermostats may be faulty.See Figure F.16, the Simplified Trigger Circuitdiagram.
9. Carefully test for 24VDC at the power PCboard at plug J7 pin 2 (lead #309)(+) to plugJ14 pin2 (lead #313)(-). See Figure F.15.
NOTE: If the 24VAC is present but the 24VDC isNOT, the power PC board may be faulty.
10. Carefully test for approximately 24VDC atplug J7 pin 2 (lead#309)(+) to plug J7 pin 4(lead#310)(-). If the 24VDC is NOT present,test for approximately 1VDC at plug J14 pin1(lead#311)(+) to plug J14 pin 2 (lead#313)(-).See Figure F.15.
NOTE: If more than 1VDC is measured, performthe Protection Board Test.
NOTE: If approximately 1VDC IS present andthe 24VDC is NOT present at leads #309 to#310, the power PC board may be faulty.
11. After all tests are completed, install the frontpanel assembly.
12. Install the case wraparound cover.
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Service and repair should be performed by only Lincoln Electric factory trained personnel.Unauthorized repairs performed on this equipment may result in danger to the technician ormachine operator and will invalidate your factory warranty. For your safety and to avoid elec-trical shock, please observe all safety notes and precautions detailed throughout this manual.
If for any reason you do not understand the test procedures or are unable to perform thetest/repairs safely, contact the Lincoln Electric Service Department for electrical troubleshoot-ing assistance before you proceed. Call 1-888-935-3877.
TEST DESCRIPTION
This test will help determine if the protection PC board is functioning properly.
MATERIALS NEEDED
5/16" Nut driverVolt/ohmmeter (Multimeter)Wiring Diagrams
TROUBLESHOOTING & REPAIRF-45 F-45
INVERTEC STT
WARNING
Note: Component locations and disassembly procedures mayvary slightly on STT II models
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TROUBLESHOOTING & REPAIRF-46 F-46
INVERTEC STT
PROTECTION BOARD TEST (continued)
FIGURE F.17 – PROTECTION PC BOARD TEST POINTS
PROTECTIONL7915-[ ]
313
311
J8 J15
315
317
314
316
TEST PROCEDURE 1. Turn off the Invertec STT and disconnect
main AC input power to the machine.
2. Using the 5/16" nut driver, remove the casewraparound cover.
3. Perform the Input Filter Capacitor DischargeProcedure. See the Maintenance section.
ELECTRIC SHOCK can kill.
• Before continuing withthe test procedure, per-form the capacitor dis-charge procedure toavoid electric shock.
4. Locate the protection PC board just in frontof the input rectifier and relay mountings.
ELECTRIC SHOCK can kill.
• With input power ON,there are high voltagesinside the machine. Donot reach into themachine or touch anyinternal part.
5. Apply the correct input power and turn themachine ON.
6. Test for approximately 1VDC from plug J8pin 1 (lead #311)(+) to plug J8 pin 3 (lead#313) (-). See Figure F.17.
A. If approximately 1VDC is present, theprotection PC board is functioning prop-erly.
B. If more than 5 VDC is measured, per-form the Capacitor Balance Test.
WARNING
WARNING
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TROUBLESHOOTING & REPAIRF-47 F-47
INVERTEC STT
FIGURE F.18 - LEADS #309, #309A AT CR1, CR2 RELAYS
CR2 CR1
309A 309
PROTECTION BOARD TEST (continued)
7. If the Capacitor Balance Test is OK andmore than 5VDC is present at leads #311 to#313 (Step 6), the protection PC board maybe faulty.
NOTE: The above voltage checks pertain onlyto the over voltage signal from the protectionPC board to the power PC board. The capaci-tor precharge circuits are also incorporatedwithin the protection PC board. If the problemhas not been identified, carefully proceed withthe following steps.
8. Remove input power to the Invertec STTmachine.
9. Perform the Input Filter Capacitor DischargeProcedure. See the Maintenance section.
ELECTRIC SHOCK can kill.
• Before continuing withthe test procedure, per-form the capacitor dis-charge procedure toavoid electric shock.
10. Locate and remove leads #309 and #309Afrom CR1 and CR2 relays. See FigureF.18.
ELECTRIC SHOCK can kill.
• With input power ON,there are high voltagesinside the machine. Donot reach into the machineor touch any internal part.
11. Apply correct input power and turn ON themachine.
12. Check for approximately 12VDC from plugJ15 pin 1 (lead #314)(+) to plug J15 pin 4(lead#315) (-). See Figure F.17.
13. Check for approximately 12VDC from plugJ15 pin 3 (lead #316)(+) to plug J15 pin 6(lead#317) (-). See Figure F.17.
14. If a low voltage is present in either steps 12or 13 (approximately 1VDC), perform theCapacitor Balance Test.
15. If the Capacitor Balance Test is OK, theprotection PC board may be faulty.
16. Be certain to replace leads #309 and #309Aonto the CR1 and CR2 relays.
17. After all tests are completed, install thecase wraparound cover.
WARNING
WARNING
NOTESF-48 F-48
INVERTEC STTRet
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TRIGGER CIRCUIT TEST
Service and repair should be performed by only Lincoln Electric factory trained personnel.Unauthorized repairs performed on this equipment may result in danger to the technician ormachine operator and will invalidate your factory warranty. For your safety and to avoid elec-trical shock, please observe all safety notes and precautions detailed throughout this manual.
If for any reason you do not understand the test procedures or are unable to perform thetest/repairs safely, contact the Lincoln Electric Service Department for electrical troubleshoot-ing assistance before you proceed. Call 1-888-935-3877.
TEST DESCRIPTION
This test includes a few quick checks to troubleshoot the machine trigger circuit. TheSimplified Trigger Circuit Diagram will enable the technician to view the trigger circuit in anabbreviated, uncomplicated format.
MATERIALS NEEDED
5/16" Nut driverVolt/ohmmeter (Multimeter)Wiring Diagram and board Schematics
TROUBLESHOOTING & REPAIRF-49 F-49
INVERTEC STT
WARNING
Note: Component locations and disassembly procedures mayvary slightly on STT II models
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TROUBLESHOOTING & REPAIRF-50 F-50
INVERTEC STT
TRIGGER CIRCUIT TEST (continued)
FIGURE F.19 – PLUG J31 LOCATION
PLUGJ31
TEST PROCEDURE
1. Turn off the Invertec STT and disconnect mainAC input power to the machine.
2. Using the 5/16" nut driver, remove the casewraparound cover.
3. Perform the Input Filter CapacitorDischarge Procedure. See the Maintenancesection.
ELECTRIC SHOCK can kill.
• Before continuing with thetest procedure, performthe capacitor dischargeprocedure to avoid electricshock.
4. Locate plug J31 at the left side of themachine. See Figure F.19.
WARNING
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TROUBLESHOOTING & REPAIRF-51 F-51
INVERTEC STT
TRIGGER CIRCUIT TEST (continued)FIGURE F.20 – 14 PIN AMPHENOL AND PLUG J31 PIN ASSIGNMENTS
KB
I
HN
LC
DM
G
E
F
JA
5. Using the ohmmeter check for approximately3.5 ohms resistance from pin "D" of the 14 pinamphenol to plug J31 pin 2 (lead #212). SeeFigure F.20, and Figure F.22, SimplifiedTrigger Circuit Diagram.
FIGURE F.21 – CONTROL PC BOARD MOLEX PLUG
J4
223
210
G27
82-[
]S
TT
CO
NT
RO
L
J1J3J2J28J27J17J5
6. Using the ohmmeter, check for approximately3.5 ohms resistance from pin "C" of the 14 pinamphenol (see Figure F.20) to plug J4 pin 9
(lead#223) at the control PC board. SeeFigure F.21 and Figure F.22, SimplifiedTrigger Circuit Diagram.
PLUG J31212
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TROUBLESHOOTING & REPAIRF-52 F-52
INVERTEC STT
TRIGGER CIRCUIT TEST (continued)FIGURE F.22 – SIMPLIFIED TRIGGER CIRCUIT DIAGRAM
FROM PROTECTIONBOARD OVERVOLTAGE
PWM OUTPUTS
TO POWERBOARD
7J6
2J6
11J4
3J4
13J36
5J36
8J33
6J34
9J4
12J4
3J31 6J22 6J4
POWER BOARD CONTROL BOARD
REMOTE PROTECTION
BOARD
14 AMPHENOL
#301
#305
#503A
#224 #210
#212
#223
#212C
#413
#405
C
D
T1 AUXILIARYTRANSFORMER
24VAC
PWM
5J4TOPOWERBOARD
2J31
3.5 ohms
3.5 ohms
STT II Only
#379
7. Using the ohmmeter check for continuity (zeroohms) from plug J31 pin 3 (lead#503A) to plugJ4 pin 6 (lead#210). See Figure F.22,Simplified Trigger Circuit Diagram.
8. If any of the resistance checks are abnormal-ly high in steps 5, 6 or 7, check for broken orloose wires, connections or "open" ther-mostats. Also check the small inductors onthe Remote Protection Board. See FigureF.22, Simplified Trigger Circuit Diagram.
ELECTRIC SHOCK can kill.
• With input power ON,there are high voltagesinside the machine. Donot reach into the machineor touch any internal part.
9. Apply the correct input power to the machineand turn ON.
10. Locate plug J6 on the power PC board. SeeFigure F. 15. in the Power Board Test.
11. Carefully check for approximately 1VDC fromplug J6 pin 2 (lead #305)(+) to plug J6 pin 7(lead #301) (-). If the approximately 1VDC ispresent the power PC board and protectionPC board are functioning properly for the trig-ger circuit to operate. If the correct DC volt-age is NOT present, perform the ProtectionBoard Test and the Power Board Test.
12. Test to make sure the T1 auxiliary trans-former is producing 24VAC. See Figure F.22,Simplified Trigger Circuit Diagram.
13. If the above tests do not reveal the problem,the control PC board or associated wiringmay be faulty. See Figure F.22, SimplifiedTrigger Circuit Diagram.
WARNING
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IGBT MODULEREMOVAL AND REPLACEMENT
Service and repair should be performed by only Lincoln Electric factory trained personnel.Unauthorized repairs performed on this equipment may result in danger to the technician ormachine operator and will invalidate your factory warranty. For your safety and to avoid elec-trical shock, please observe all safety notes and precautions detailed throughout this manual.
If for any reason you do not understand the test procedures or are unable to perform thetest/repairs safely, contact the Lincoln Electric Service Department for electrical troubleshoot-ing assistance before you proceed. Call 1-888-935-3877.
DESCRIPTION
The following procedure will aid the technician in the removal and replacement of the IGBTmodule located in the lower tray assembly.
MATERIALS NEEDED
5/16" Nut driverPhillips head screw driver7/16" wrenchNeedle nose pliers1/2" Wrench12mm Wrench3/16" Allen type wrenchDow Corning 340 Heat Sink Compound (Lincoln E1868).Silicone Rubber RTV Coating (Lincoln E2861 or Dow 3140)
TROUBLESHOOTING & REPAIRF-53 F-53
INVERTEC STT
WARNING
Note: Component locations and disassembly procedures mayvary slightly on STT II models
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TROUBLESHOOTING & REPAIRF-54 F-54
INVERTEC STT
IGBT MODULE REMOVALAND REPLACEMENT (continued)
FIGURE F.23 – OUTPUT CHOKE LEAD DISCONNECTION
LOWERTRAYAREA
OUTPUT CHOKE/IGBT MODULESPLICED CONNECTION
PROCEDURE
1. Turn off the Invertec STT and disconnect mainAC input power to the machine.
2. Using the 5/16" nut driver, remove the casewraparound cover.
3. Perform the Input Filter CapacitorDischarge Procedure. See the Maintenancesection.
ELECTRIC SHOCK can kill.
• Before continuing with thetest procedure, performthe capacitor dischargeprocedure to avoid electricshock.
4. Locate the lead connection splice from theoutput choke to the IGBT module. Removethe insulating sleeve. Using the 7/16" wrenchdisconnect the lead splice. Thread the lowerlead down into the lower tray assembly area.See Figure F.23.
WARNING
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TROUBLESHOOTING & REPAIRF-55 F-55
INVERTEC STT
IGBT MODULE REMOVALAND REPLACEMENT (continued)
FIGURE F.24 – PLUG J1 DISCONNECTION
LOWERTRAYAREA
OUTPUT CHOKE/IGBT MODULESPLICED CONNECTION
J1 CURRENTSENSING PLUG
5. Disconnect the current sensing plug J1 fromthe control PC board. Carefully remove plug
J1 and associated leads from the control PCboard compartment. See Figure F.24.
FIGURE F.25 – PLUG J22 DISCONNECTION
PLUG J22
6. Locate and disconnect plug J22 from thewiring harness. See Figure F.25.
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TROUBLESHOOTING & REPAIRF-56 F-56
INVERTEC STT
IGBT MODULE REMOVALAND REPLACEMENT (continued)
FIGURE F.26 – STT PLACED ON ITS RIGHT SIDE
MOUNTINGBOLTS (5)
7. Carefully lift and tilt the Invertec STTmachine onto its right side. See Figure F.26.
8. Using the 7/16" wrench, remove the fivebolts holding the lower tray assembly to thecase bottom.
9. Carefully slide out and support the lower trayassembly.
10. Using the needle nose pliers, remove thestrain relief holding the J22 lead harness tothe case bottom.
11. Using the 1/2" wrench, remove the IGBTcable from the negative output terminal.
12. Carefully remove the lower tray assemblyclear from the machine.
13. Remove the rubber RTV coating from theIGBT module.
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TROUBLESHOOTING & REPAIRF-57 F-57
INVERTEC STT
IGBT MODULE REMOVALAND REPLACEMENT (continued)FIGURE F.27 – IGBT MODULE CONNECTIONS
E
E
IGBTMODULE
C
G
STT IIFor steps 14-18, see Figure F.27.
14. Using the phillips head screw driver, removethe small leads from the small "E" and "B"terminals. Note lead placement for reassem-bly.
15. Using the 12mm wrench, remove the largelead and the #289 lead from the large "E" ter-minal. Note lead placement for reassembly.
16. Using the 12mm wrench, remove the largelead and the #287 lead from the large "C"terminal. Note lead placement for reassem-bly.
17. Using the 3/16" Allen type wrench, removethe four socket head cap screws that mountthe module to the heat sink.
18. Carefully remove the IGBT module.
19. Upon reassembly, use Dow Corning 340Heat Sink Compound (Lincoln E1868)between the module and the heat sink.
20. Mount the new module using the sockethead cap screws and torque to 35 inchpounds.
Note: The torque should be rechecked afterthree hours.
21. Using the 12mm wrench, assemble the largelead and the smaller #289 lead to the large"E" terminal. Torque to 86 inch pounds.
22. Using the 12mm wrench, assemble the largelead and the smaller #287 lead to the large"C" terminal. Torque to 86 inch pounds.
23. Using the phillips head screw driver,reassemble the small leads to the small "E"and "G" terminals. Torque to 13 inchpounds.
24. Apply the Silicone Rubber RTV Coating(Lincoln E2861 or Dow 3140) to the termi-nals and lead connections as was previouslyremoved.
25. Replace the lower tray assembly.
26. Connect plug J22 to the wiring harness andplug J1 to the control PC board.
27. Connect the lead splice between the outputchoke and the IGBT module.
28. Install the case wraparound cover.
NOTESF-58 F-58
INVERTEC STTRet
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SWITCH BOARDREPLACEMENT
Service and repair should be performed by only Lincoln Electric factory trained personnel.Unauthorized repairs performed on this equipment may result in danger to the technician ormachine operator and will invalidate your factory warranty. For your safety and to avoid elec-trical shock, please observe all safety notes and precautions detailed throughout this manual.
If for any reason you do not understand the test procedures or are unable to perform thetest/repairs safely, contact the Lincoln Electric Service Department for electrical troubleshoot-ing assistance before you proceed. Call 1-888-935-3877.
DESCRIPTION
This procedure will aid the technician in the removal and replacement of the switch boards.
MATERIALS NEEDED
5/16" Nut driver7/16" Wrench3/16" Allen type wrench3/16" Socket wrenchDow Corning 340 Heat Sink Compound (Lincoln E1868)ANALOG Ohmmeter
TROUBLESHOOTING & REPAIRF-59 F-59
INVERTEC STT
WARNING
Note: Component locations and disassembly procedures mayvary slightly on STT II models
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TROUBLESHOOTING & REPAIRF-60 F-60
INVERTEC STT
SWITCH BOARD REPLACEMENT (continued)
FIGURE F.28 – SWITCH BOARD REMOVAL
PROCEDURE
NOTE: If a test indicates that a switch board isdefective, both switch boards must be replaced atthe same time. In addition to replacing the switchboards, replace capacitors C1 and C2 if the fol-lowing conditions exist:
a. The machine was operating from 380 VACor higher when the failure occurred.
b. Burned areas are visible on the switchboards.
1. Turn off the Invertec STT and disconnect mainAC input power to the machine.
2. Using the 5/16" nut driver, remove the casewraparound cover.
3. Perform the Input Filter Capacitor DischargeProcedure. See the Maintenance section.
ELECTRIC SHOCK can kill.
• Before continuing with thetest procedure, perform thecapacitor discharge proce-dure to avoid electricshock.
4. Carefully disconnect the leads at the top of theswitch board.
5. Using the 3/16" socket wrench, remove thefour cap screws from the switch board. SeeFigure F.28.
WARNING
SOCKETHEADSCREWS
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TROUBLESHOOTING & REPAIRF-61 F-61
INVERTEC STT
SWITCH BOARD REPLACEMENT (continued)
6. Using the 7/16" wrench, remove the two hexhead capacitor screws located in the centerof the switch board. Hold the board firmly asyou remove the screws.
7. Carefully remove the switch board.
8. Clean the heat sink surfaces thoroughly toremove all the heat sink compound. (Duringmachine operation, this compound helpsconduct heat from the switch board to theheat sinks.
9. Apply a thin layer (.002") of Dow Corning340 Heat Sink Compound (Lincoln E1868) tothe mounting surfaces of the new switchboard and to the capacitor terminals. DONOT allow the compound to enter themounting screw holes. It can distort thetorque values.
10. Prepare to mount the new switch board onthe heat sink by first lining up the mountingholes. Then press the switch board intoplace.
11. Insert each of the four socket head screwsinto the mounting holes. Thread them fingertight. The threads are soft -- be careful no tocross-thread them.
12. Insert each of the two hex head screws intothe capacitor terminal holes. Thread themfinger tight. Be careful not to cross-thread thescrews.
13. Torque both sets of screws in 10 inch-poundincrements. Use a diagonal tighteningsequence. Torque the four socket headscrews to 44 inch-pounds (5 Nm). Torque thetwo hex head screws to 55 inch-pounds (6Nm).
Failure to connect the switch board leads correct-ly can result in damage to the Invertec STTmachine when power is applied.
14. Reconnect all the leads to the switch board.Be sure each lead is connected to the correctterminal.
15. Perform the Test after Repair of SwitchBoards and/or Capacitors.
NOTE: Always make sure that the switch boardsare changed in matched pairs. Never mix an oldstyle switch board (different part number) withnew style (new part number).
CAUTION
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TROUBLESHOOTING & REPAIRF-62 F-62
INVERTEC STT
SWITCH BOARD REPLACEMENT (continued)
TEST AFTER REPAIR OF SWITCHBOARDS AND/OR CAPACITORS
The following test must be performed after theswitch boards and/or the capacitors have beenreplaced.
NOTE: Always make sure that switch boards arechanged in matched pairs. Never mix an old style(different part number) switch board with a newstyle (new part number).
TEST PROCEDURE
1. Turn main power OFF.
2. Perform Input Filter Capacitor DischargeProcedure. See the Maintenance section.
ELECTRIC SHOCK can kill.
• Before continuing with thetest procedure, performthe capacitor dischargeprocedure to avoid electricshock.
3. Connect a shorting conductor across termi-nals 14 and 53 of the protection PC board.See Figure F.29.
4. Set an ANALOG ohmmeter to X1000 rangeand place the probes on terminals 9 (+) and12 (–) of one switch board. The meter willshow the capacitors charging up and maytake a minute or so to stabilize. The finalmeter reading should not exceed 8600 ohms(8.6 on the scale).
5. Test the other switch board the same way.
NOTE: Repeat the Input Filter CapacitorDischarge Procedure.
6. Remove the shorting conductor set up in step3.
7. Replace 20 amp fuses with 5-amp fuses inthe input supply fuse holders.
NOTE: These fuses should be installed to pro-tect against excessive current flow caused by ashort circuit during the procedure.
WARNING
FIGURE F.29 — SHORTING TERMINALS 14 AND 53 OF PROTECTION BOARD
L7915-[ ] PROTECTION
53 14
JUMPER TERMINALS
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TROUBLESHOOTING & REPAIRF-63 F-63
INVERTEC STT
SWITCH BOARD REPLACEMENT (continued)
ELECTRIC SHOCK can kill.
• With input power ON, thereare high voltages in themachine. Do not reachinto the machine or touchany internal part.
8. With the machine connected for 440/460 voltoperation and the proper input voltageapplied, turn on input power to the machine.
9. With the output free of a load, check open cir-cuit voltages of the output. Voltage should be85 VDC maximum.
10. Remove input power. Then remove the 5-amp fuses from the input supply fuse hold-ers.
11. Install 20-amp fuses and test under load.
NOTE: A resistive-type grid load bank is recom-mended.
14. Perform Retest After Repair.
WARNING
NOTESF-64 F-64
INVERTEC STTRet
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CAPACITOR REMOVAL ANDREPLACEMENT PROCEDURE
Service and repair should be performed by only Lincoln Electric factory trained personnel.Unauthorized repairs performed on this equipment may result in danger to the technician ormachine operator and will invalidate your factory warranty. For your safety and to avoid elec-trical shock, please observe all safety notes and precautions detailed throughout this manual.
If for any reason you do not understand the test procedures or are unable to perform thetest/repairs safely, contact the Lincoln Electric Service Department for electrical troubleshoot-ing assistance before you proceed. Call 1-888-935-3877.
DESCRIPTION
This procedure will aid the technician in the removal and replacement of the input filter capac-itors C1 and C2.
MATERIALS NEEDED
5/16" Nut driverSlot head screw driver7/16" WrenchNeedle nose pliers1/2" Wrench
TROUBLESHOOTING & REPAIRF-65 F-65
INVERTEC STT
WARNING
Note: Component locations and disassembly procedures mayvary slightly on STT II models
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TROUBLESHOOTING & REPAIRF-66 F-66
INVERTEC STT
CAPACITOR REMOVAL AND REPLACEMENT PROCEDURE (continued)
FIGURE F.30 – OUTPUT CHOKE LEAD DISCONNECTION
LOWERTRAYAREA
OUTPUT CHOKE/IGBT MODULESPLICED CONNECTION
PROCEDURE
1. Turn off Invertec STT and disconnect main ACinput power to the machine.
2. Using the 5/16" nut driver, remove the casewraparound cover.
3. Perform the Input Filter CapacitorDischarge Procedure. See the Maintenancesection.
ELECTRIC SHOCK can kill.
• Before continuing with thetest procedure, perform thecapacitor discharge proce-dure to avoid electricshock.
4. Locate the lead connection splice from theoutput choke to the IGBT module. Removethe insulating sleeve. Using the 7/16" wrenchdisconnect the lead splice. Thread the lowerlead down into the lower tray assembly area.See Figure F.30.
WARNING
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TROUBLESHOOTING & REPAIRF-67 F-67
INVERTEC STT
CAPACITOR REMOVAL AND REPLACEMENT PROCEDURE (continued)
FIGURE F.31 – PLUG J1 DISCONNECTION
LOWERTRAYAREA
OUTPUT CHOKE/IGBT MODULESPLICED CONNECTION
J1 CURRENTSENSING PLUG
5. Disconnect the current sensing plug J1 fromthe control PC board. Carefully remove plugJ1 and associated leads from the control PCboard compartment.
FIGURE F.32 – PLUG J22 DISCONNECTION
PLUG J22
6. Locate and disconnect plug J22 from thewiring harness. See Figure F.32.
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TROUBLESHOOTING & REPAIRF-68 F-68
INVERTEC STT
CAPACITOR REMOVAL AND REPLACEMENT PROCEDURE (continued)
FIGURE F.33 – STT PLACED ON ITS RIGHT SIDE
MOUNTINGBOLTS (5)
7. Carefully lift and tilt the Invertec STTmachine onto its right side. See Figure F.33.
8. Using the 7/16" wrench, remove the fivebolts holding the lower tray assembly to thecase bottom.
9. Carefully slide out and support the lower trayassembly.
10. Using the needle nose pliers, remove thestrain relief holding the J22 lead harness tothe case bottom.
11. Using the 1/2" wrench, remove the IGBTcable from the negative output terminal.
12. Carefully remove the lower tray assemblyclear from the machine and set aside.
13. Carefully disconnect the leads at the top ofthe switch board.
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TROUBLESHOOTING & REPAIRF-69 F-69
INVERTEC STT
CAPACITOR REPLACEMENT
NOTE: Capacitors must always be replaced inmatched sets (C1 and C2 as a set).
When replacing Capacitors, remove the entireFET heat sink assembly, including the capacitorsand switch board, as a unit.
Disassemble and reassemble only one unit at atime. Use the other unit as a model duringreassembly so that all parts are reinstalled prop-erly.
14. Remove the two 3/8” hex head nuts from thetop of the through-bolts. The hex nuts arelocated on top of the fan shroud. See FigureF.34.
CAPACITOR REMOVAL AND REPLACEMENT PROCEDURE (continued)
FIGURE F.34 – REMOVING HEX HEAD NUTS OF THROUGH-BOLTS
HEX NUT
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TROUBLESHOOTING & REPAIRF-70 F-70
INVERTEC STT
15. Place the machine on its side as shown inFigure F.35. Slide the plastic retaining insu-lators that go through the base of themachine to one side. Pull the through-boltsout of the machine, being careful to save allthe insulation and standoff material. Setaside for reassembly.
16. Remove the switch board and capacitorassembly from the machine.
FIGURE F.35 – REMOVING THROUGH-BOLTS
CAPACITOR REMOVAL AND REPLACEMENT PROCEDURE (continued)
PLASTIC RETAININGINSULATORS
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TROUBLESHOOTING & REPAIRF-71 F-71
INVERTEC STT
17. Remove the two 7/16” hex bolts that hold thecapacitor to the switch board. See FigureF.36.
18. Loosen the set screw of the capacitor clampring and remove the capacitor from the clampring. See Figure F.37.
FIGURE F.36 – REMOVING CAPACITOR NUTS
CAPACITOR REMOVAL AND REPLACEMENT PROCEDURE (continued)
17. Remove the two 7/16” hex bolts that hold thecapacitor to the switch board. See FigureF.36.
18. Loosen the set screw of the capacitor clampring and remove the capacitor from the clampring. See Figure F.37.
FIGURE F.37 – LOOSENING THE CLAMP RING SET SCREW
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TROUBLESHOOTING & REPAIRF-72 F-72
INVERTEC STT
19. Install the new capacitor and tighten the two7/16” hex bolts to a torque of 55 inch-pounds(6 Nm). Tighten these bolts in increments of10 inch-pounds, alternating between the twobolts. Capacitor installation is complete. SeeFigure F.38.
Proper capacitor polarity must be noted whenattaching the capacitor to the switch boardassembly.
20. Install the switch board and capacitorassembly into the machine. Take specialcare that ALL insulators and sleevings are intheir proper positions. See Figure F.38.
21. Install the lower tray assembly and all previ-ously disconnected loads and plugs.
22. Perform the Test After Repair of SwitchBoards and/or Capacitors.
NOTE: Always make sure that the switch boardsare changed in matched pairs. Never mix an oldstyle switch board (different part number) withnew style (new part number).
INPUT FILTER CAPACITOR CONDITIONING
If the machine will not produce output whenturned on and the following two conditions exist:
The machine is connected to operate at aninput voltage of 380 VAC or higher and
Power has not been applied to the machine fora long period of time (many months). Then. . .
The Input Filter Capacitor Protection Circuit couldhave been activated and prevented output. Thismeans the Input Filter Capacitors must be condi-tioned.
The Input Filter Capacitor Protection Circuit mon-itors the voltage across input filter capacitors C1and C2. When it senses an overvoltage condi-tion, the protection circuit will prevent themachine from operating.
To condition the Input Filter Capacitors:
1. Turn main power OFF.
2. Remove any load and do not load machineuntil conditioning procedure is complete.
3. Turn main power ON.
4. Let the unloaded machine sit for 30 minutes.
5. Turn main power OFF.
6. Turn main power ON.
NOTE: The machine should be ready to operate,and the protection circuit should have automati-cally reset once the capacitors have been condi-tioned and capacitor voltage has reached theacceptable operating level.
FIGURE F.38 – COMPLETE SWITCH BOARD ASSEMBLY READY FOR INSTALLATION
CAPACITOR REMOVAL AND REPLACEMENT PROCEDURE (continued)
CAUTION
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OUTPUT RECTIFIER REMOVAL AND REPLACEMENT
Service and repair should be performed by only Lincoln Electric factory trained personnel.Unauthorized repairs performed on this equipment may result in danger to the technician ormachine operator and will invalidate your factory warranty. For your safety and to avoid elec-trical shock, please observe all safety notes and precautions detailed throughout this manual.
If for any reason you do not understand the test procedures or are unable to perform thetest/repairs safely, contact the Lincoln Electric Service Department for electrical troubleshoot-ing assistance before you proceed. Call 1-888-935-3877.
DESCRIPTION
This procedure will aid the technician in the removal and replacement of the output diode heatsink assembly.
MATERIALS NEEDED
5/16" Nut driver3/8" Nut driver7/16" WrenchSlot head screw driverDow Corning 340 Heat Sink Compound (Lincoln E1868)
TROUBLESHOOTING & REPAIRF-73 F-73
INVERTEC STT
WARNING
Note: Component locations and disassembly procedures mayvary slightly on STT II models
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TROUBLESHOOTING & REPAIRF-74 F-74
INVERTEC STT
OUTPUT RECTIFIER REMOVAL AND REPLACEMENT (continued)
FIGURE F.39 – CHOKE LEAD/HEAT SINK CONNECTION
CHOKE LEAD
HEAT SINK TAB
PROCEDURE
1. Turn off Invertec STT and disconnect mainAC input power to the machine.
2. Using the 5/16" nut driver, remove the casewraparound cover.
3. Perform the Input Filter CapacitorDischarge Procedure. See the Maintenancesection.
ELECTRIC SHOCK can kill.
• Before continuing withthe test procedure, per-form the capacitor dis-charge procedure toavoid electric shock.
4. Using the slot head screw driver, loosen theinput cable strain relief.
5. Using the 5/16" nut driver, remove the fourscrews securing the case back to the inter-nal horizontal baffles.
6. Carefully pull the case back away from theoutput rectifier assembly.
NOTE: The case back will NOT detach fromthe case bottom.
7. Using the 7/16" wrench, remove the fourbolts and washers mounting the fan motorbracket to the top horizontal baffle.Carefully set the fan and motor assemblyaside. Note insulation placement forreassembly.
NOTE: The fan motor leads do NOT have tobe cut.
8. Using the 7/16" wrench, remove the chokelead from the heat sink tab. See Figure F.39.
WARNING
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TROUBLESHOOTING & REPAIRF-75 F-75
INVERTEC STT
OUTPUT RECTIFIER REMOVAL AND REPLACEMENT (continued)
FIGURE F.40 – MAIN TRANSFORMER DIODE CONNECTIONS
MAINTRANSFORMERSECONDARYLEADS
9. Remove the two sleevings from the diodeconnections at the main transformer. SeeFigure F.40.
10. Using the 7/16" wrench, remove the diodeleads from the main transformer sec-ondary leads. Note washer and leadplacement for reassembly.
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TROUBLESHOOTING & REPAIRF-76 F-76
INVERTEC STT
OUTPUT RECTIFIER REMOVAL AND REPLACEMENT (continued)
FIGURE F.41 – SWITCH BOARD/CAPACITOR ASSEMBLY THROUGH-BOLTS
THROUGH-BOLTS
11. Using the 3/8" nut driver, remove the rearnuts and washers from the switchboard/capacitor assembly through-bolts.See Figure F.41.
12. Using the 3/8" nut driver, loosen the frontnuts from the switch board/capacitorassembly through-bolts.
13. Carefully lift the horizontal baffle awayfrom the upper tabs of the output rectifierheat sink assembly.
14. Slide the heat sink assembly to the right(facing the back of the machine) to disen-gage the bottom tabs from the lower hori-zontal baffle.
15. Carefully remove the output rectifier heatsink assembly and leads from the STTmachine.
16. Remove the nut that secures each diodethat is to be replaced.
NOTE: The output diodes must be replaced inmatched sets.
17. Before mounting the new diode sets, cleanand brighten the mounting surfaces ofboth the diode sets and the heat sink withfine steel wool.
18. Apply an even coating of DOW Corning340 Heat Sink Compound to the mountingsurfaces of the diodes that contact theheat sink. This compound layer should beless than .001 inch thick. DO NOT applythe compound to the diode studs ormounting nut threads.
19. Insert the diode sets into the mountinghole and tighten the diode mounting nutsto a torque of 25 inch-pounds (3 Nm).
20. Replace the rectifier heat sink assembly,leads and connections that were previous-ly removed. Install the fan and motorassembly (note insulation placement).Install the case back and the case wrap-around cover.
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TROUBLESHOOTING & REPAIRF-77 F-77
INVERTEC STT
RETEST AFTER REPAIRRetest the INVERTEC STT:
• If it fails any test and the test requires removing or replacing any mechanical part that could affect the machine'selectrical characteristics.
OR
• If you repair or replace any electrical components.
MAXIMUM INPUT IDLE AMPS AND IDLE WATTS
INPUT CURRENT @ IDLE 3.5 AMPS
INPUT POWER @ IDLE 800 WATTS
MINIMUM ACCEPTABLE OUTPUT (AT MAXIMUM BACKGROUND SETTING)[STATIC GRID LOAD]
CONTROL MODE AMPS VOLTS
BACKGROUND 140 20
OPEN CIRCUIT VOLTAGE RANGE
73 TO 85 VDC
INPUT FILTER CAPACITOR CONDITIONING
If the machine will not produce output when turned onand the following two conditions exist:
The machine is connected to operate at an inputvoltage of 380 VAC or higher and
Power has not been applied to the machine for along period of time (many months). Then. . .
The Input Filter Capacitor Protection Circuit could havebeen activated and prevented output. This means theInput Filter Capacitors must be conditioned.
The Input Filter Capacitor Protection Circuit monitorsthe voltage across input filter capacitors C1 and C2.When it senses an overvoltage condition, the protec-tion circuit will prevent the machine from operating.
To condition the Input Filter Capacitors:
1. Turn main power OFF.
2. Remove any load and do not load machine untilconditioning procedure is complete.
3. Turn main power ON.
4. Let the unloaded machine sit for 30 minutes.
5. Turn main power OFF.
6. Turn main power ON.
NOTE: The machine should be ready to operate, andthe protection circuit should have automatically resetonce the capacitors have been conditioned and capac-itor voltage has reached the acceptable operatinglevel.
ENVIRONMENTAL PROTECTION
High voltage connections are covered with an RTVsealant to prevent malfunction in severe environments.Sealant must be applied to connections which havebeen opened or otherwise lost their protection. A non-corrosive, electronic grade sealant such as DowCorning 3140, 3145, or 738; Columbus Adhesives0172; or GE RTV-162 is recommended. Sealant mayalso be purchased from Lincoln Electric (order E2519Silicone Rubber RTV Coating). Apply sealant aftermachine is repaired and tested. All five terminals of theinput rectifier require this type of sealant.
TROUBLESHOOTING & REPAIRF-78 F-78
INVERTEC STTRet
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INVERTEC STT
Section G-1 Section G-1TABLE OF CONTENTS- ELECTRICAL DIAGRAMS SECTION -
Electrical Diagrams ...............................................................................................Section G
Wiring Diagram - Entire Machine - Codes 10151-10153 - (G2773) . . . . . . . . . . . . . .G-2
Wiring Diagram - Entire Machine - Codes 10381-10383 - (G3136) . . . . . . . . . . . . . .G-3
Wiring Diagram - Entire Machine - Codes 11090-11092 - (G4500) . . . . . . . . . . . . . .G-4
Wiring Diagram - Entire Machine - Codes 11115-11116 - (G4557) . . . . . . . . . . . . . . .G-5
Schematic - Control PC Board - Codes 10151-11092 - (G2781 Sheet 1) . . . . . . . . .G-6
Schematic - Control PC Board - Codes 10151-11092 - (G2781 Sheet 2) . . . . . . . . .G-7
PC Board Assembly - Control - Codes 10151-11092 - (G2782) . . . . . . . . . . . . . . . . .G-8
Schematic - Control PC Board - Codes 11115-11116 - (G4649 Sheet 1) . . . . . . . . . .G-9
Schematic - Control PC Board - Codes 11115-11116 - (G4649 Sheet 2) . . . . . . . . .G-10
PC Board Assembly - Control - Codes 11115-11116 - (G4648) . . . . . . . . . . . . . . . . .G-11
Schematic - Power PC Board - All Codes - (M16018) . . . . . . . . . . . . . . . . . . . . . . .G-12
PC Board Assembly - Power - All Codes - (L8033) . . . . . . . . . . . . . . . . . . . . . . . . . .G-13
Schematic - Darlington Drive Board - Codes 10151-10383 - (M17581) . . . . . . . . . .G-14
PC Board Assembly - Darlington Drive - Codes 10151-10383 - (G2778) . . . . . . . . .G-15
Schematic - IGBT Drive Board - Codes 11090-11116 - (L12144) . . . . . . . . . . . . . . .G-16
PC Board Assembly - IGBT Drive - Codes 11090-11116 - (L12145) . . . . . . . . . . . . .G-17
Schematic - Switch Board - All Codes - (L8440) . . . . . . . . . . . . . . . . . . . . . . . . . . . .G-18
PC Board Assembly - Switch - All Codes - (L8441) . . . . . . . . . . . . . . . . . . . . . . . . .G-19
Schematic - Driver Board - All Codes - (S20799) . . . . . . . . . . . . . . . . . . . . . . . . . . .G-20
PC Board Assembly - Driver - All Codes - (L9134) . . . . . . . . . . . . . . . . . . . . . . . . . .G-21
Schematic - Protection PC Board - Codes 10151-11092 - (M16097) . . . . . . . . . . . .G-22
PC Board Assembly - Protection - Codes 10151-11092 - (L7915) . . . . . . . . . . . . . .G-23
Schematic - Protection PC Board - Codes 11115-11116 - (M20352) . . . . . . . . . . . .G-24
PC Board Assembly - Protection - Codes 11115-11116 - (L12235) . . . . . . . . . . . . . .G-25
Schematic - Current Sense PC Board - All Codes - (S21410) . . . . . . . . . . . . . . . . .G-26
PC Board Assembly - Current Sense - All Codes - (M17591) . . . . . . . . . . . . . . . . . .G-27
Schematic - Remote Protection PC Board - All Codes - (M17609) . . . . . . . . . . . . . .G-28
PC Board Assembly - Remote Protection - All Codes - (L9657) . . . . . . . . . . . . . . . .G-29
G-2ELECTRICAL DIAGRAMS
INVERTEC STT & STT II
+
-
ELECTRICAL SYMBOLS PER E1537
H1
T1
FANMOTOR
GFEJAIKCDML
BN
H
7576773132414224818221GNDSPARE
42VAC
T3 CURRENTTRANSFORMER
1
4
T2MAIN TRANSFORMER
R3
OFFON
H1 TP1
TP3TP2
I
I5
8
D1D2D3
CHOKE
L3
CONTROLBOARD
10K2W R11
307308309310
302303
304
POWERBOARD
(VIEWED FROM COMPONENT SIDE OF BOARD)NOTES:
TRIGGER
INPUTPER N.A.
POWERS1
1
2
3
1
78
J7
J6
CB1
504
43A
AUXILIARYTRANSFORMER
245613
N.E.
CW (MAX)
9
10
F
F S
SS
TOPOUTSIDE
BOTTOMINSIDE
S
S
SF
F
TOP
TOPINSIDE
BOTTOMOUTSIDE
7
68
4
5
CONTROL
211A
212B150 5W
FANTHERMOSTAT
H2
H3
H4
FBOTTOM
F
212A
W
V
U
H1
2120V
24V
42V
18V1
4
2
3
.001/400
COLOR CODE:
R = RED
6H5
2
3
6
4
7
8
5
502
Y
301
D4D5
D11D10D9D8D7
N.E.
210
6AMP
H2
H3
H4
A
9C
W
B
G
A
FOR THREE PHASE INPUT: CONNECT GREEN LEAD TO GROUND PER NATIONAL ELECTRIC CODE.CONNECT BLACK, RED & WHITE LEADS TO SUPPLY CIRCUIT.
WRAP RED LEAD WITH TAPE TO PROVIDE 600V. INSULATION.
FOR THREE PHASE INPUT: GROUND MACHINE PER NATIONAL AND LOCAL ELECTRICAL CODES.CONNECT TERMINALS U, V & W TO SUPPLY CIRCUIT.
CONNECT TERMINALS U & W TO SUPPLY CIRCUIT.
N.D. PLACE "A" LEAD ON APPROPRIATE CONNECTION FOR INPUT VOLTAGE.CONNECTION SHOWN IS FOR 440-460V OPERATION.
CONNECT BLACK & WHITE LEADS TO SUPPLY CIRCUIT.FOR SINGLE PHASE INPUT: CONNECT GREEN LEAD TO GROUND PER NATIONAL ELECTRIC CODE.
FOR SINGLE PHASE INPUT: GROUND MACHINE PER NATIONAL AND LOCAL ELECTRICAL CODES.
W = WHITE
B = BLACKG = GREEN
Y = YELLOW
H6
N.D.
R
H1
+ ARC
- ARC102W
C4
.001/400
9D
H1 H3
H3230V
415V
440-460V
200-208V
220-
380-
R2C3
102W
Y Y
3051234
J14311313
A
4 AMPSLOWBLOW
N.A.
N.B. SINCE COMPONENTS OR CIRCUITRY OF A PRINTED CIRCUIT BOARD MAY CHANGE WITHOUT AFFECTING
N.E. D1 THRU D5 OUTPUT DIODES ARE A MATCHED SET.
N.F. R1, R9 BLEEDER RESISTORS ARE A MATCHED SET. N.G. C1, C2 CAPACITORS ARE A MATCHED SET. N.H. PLACE SWITCH IN APPROPRIATE POSITION FOR INPUT VOLTAGE.
THE INTERCHANGEABILITY OF A COMPLETE BOARD, THIS DIAGRAM MAY NOT SHOW THE EXACTCOMPONENTS OR CIRCUITRY HAVING A COMMON CODE NUMBER.
D7 THRU D11 OUTPUT DIODES ARE A MATCHED SET.
CONNECTION SHOWN IS FOR 380-460V OPERATION.
12D
INPUTRECTIFIER D13
10K2W
CW (MAX)
CONTROL
BACKGROUNDMETER
METER
1
J2
11
8
10
4
9
3
2
7
13
126
14
5
BACKGROUND
BOARD
4
31
2
42
1
3
CURRENTSENSE
J1
J18DARLINGTON
MODULE
DARLINGTONBOARDDRIVE
J13
BE
1
23
6
4
5
J12
J5
J3
910
1
2
34
56
1. FOR MACHINES SUPPLIED WITH INPUT CABLE
2. FOR MACHINES NOT SUPPLIED WITH INPUT CABLE
1234
VOLTAGESENSECONNECTION
J19
1
18V
18V
AUXILIARYTRANSFORMER
115V
10V
18VR
W
R
B
B
U
U
E C
D7
U = BLUE
212A
212
501504
T4
275
351350
352353354355356357358
358
359
359
360
360
361
361
362
362
363
363
290
291
J21
2
93
4
12
13
N
O
12
43
67
5
8
109
R12
J18, J37 J6, J27, J33
J19
J15, J35
210A224
20/400C8
287
288A
288B
289A
289B
364365366
368369
372
376
9-13-96
G2773
NO
O = ORANGEN = BROWN
123456
123456
354355
356357
10K2W
CW (MAX)
CONTROLHOT START
R13
WIRE SIZE
WIREFEEDER
CB2
BOARD
+
12
C1
R4
R52525W2525W
9 5
8
+
12
2525W2525W
9
C2
R6
R7 4
1R1
750025W
9A
308307
402, 404
401, 403
4,5
1, 8
R
R W R W401, 403
1, 8
4, 5402, 404
SWITCH+
-
+
-
SWITCH
DRIVERBOARD
416 3
J10
2 5
BOARD
1
23
4
52
14
51
53
14
J8
PROTECTION52
2200 F450V
N.G.
N.F.
N.G.
2200 F450V
(LEFT)
BOARD(RIGHT)
12B
9B9B
R9
9A
5312A
H5
750025W
52
1
2
34
5
6
314315
317
J15
N.F.
12A
12B
51
41 32J11
73
21
812
1314
J16
9D
3 6 4 1
J9
25
12B12D
501
115V
1110371 371A
374A374
J22
240
241
242243
244
245
246
O
O
18V
6V
N
N
240241242
3
4
5
6
1213
714
1
2
8
9
1011
303302304275
371A374A243244
J27
1112
J4
374
370371
367
J28
371374
1234
1516
364
365
366
(+)
(-)
367
368
369
367A
367A
WIRE TYPESTAINLESSMILD
JBCGADFHEI
TRIGGER
GND
.045.035
BG
PB
10K
10K
OPTIONALREMOTEINTERFACE
115VAC
3
2
5
4
1
U
W
R
R
Y
N
Y
2
1 32
33
32C
33C
32A32B
33A33B
78
1516
J22
2 300W289
288
2 300W
J33
223 7
J34
33C
1
2
3
4
5
643B
31A
J35
42
33D6AMP
J36
1234
J37
J30
J31
503A
R14
8
21
67
3
4
5
372
376374
370371
62371
8
54
109
61
584
32
J24 J23
J26 J25
353352
351350
123456
123456
42VAC
115VAC
J39
1
2
4
3
67
5
8
10
9
11
12
502
210
223
Y
305245
211A212C
Y
246
301
J17
503
503A
212C43A
212B32C
3
12
10912411
146
135
168157
J38
503
REMOTEPROTECTION BOARD
S2
S3
(-)
(+)
THERMALOVERLOADINDICATOR
R13
J10, J13,J1, J8, J3, J9,
J5, J7, J34
J2, J36
J38 J39
PINOUT OF FRONT PANEL CONNECTORS (REAR VIEW)
P30 J30 P29, P31 J29. J31 P21 J21
P22 J22
INLINE CONNECTOR CAVITY NUMBERING SEQUENCE(VIEWED FROM WIRE SIDE OF CONNECTOR)
J23J24J25J26
P.C. BOARD CONNECTOR CAVITY NUMBERING SEQUENCE
METER PINOUT (VIEWED FROM BACK OF METER)
BWW
B
R
WB
BW
R
W
RB
B
PEAKCURRENT
PEAKCURRENT
B
WB
R
N.I. DENOTES A TWISTED WIRE PAIR OR GROUP.
N.J.
RW W
52
316
31131314
309
310CR1
9A
9A
9A
9A
53
9D
N.H.
9C
12C
9B
12A9B
12A
9B
S7RECONNECT
9D
12C12D
309A
310A
309310
CR2 309A
310A
12D
52
9B
12B51
12B
12B12B 12B
12B
14
6224
503A
224A
J22 THERMOSTAT
DARLINGTONHEATSINK
W
W
C
B
A
C
B
A
D
F
C
B
A
503B
J11, J12, J14
J4, J17 J16, J28
401402403
404
405
406
407
408
409410
411
412
413
414
415
416
C
B
A
C
B
A
LOAD
LINE
POWER LINEFILTER
ASSEMBLY
N.L.
N.K.
N.K. NOT PRESENT ON EUROPEAN VERSIONS, CODE 10309 AND HIGHER.N.L. PRESENT ON EUROPEAN VERSIONS, CODE 10309 AND HIGHER.
N.J. NOT PRESENT ON EUROPEAN VERSIONS.
TOROIDALCOREN.L.
G-2R
etur
nto
Sec
tion
TOC
Ret
urn
toS
ectio
nTO
CR
etur
nto
Sec
tion
TOC
Ret
urn
toS
ectio
nTO
C
Ret
urn
toM
aste
rTO
CR
etur
nto
Mas
ter
TOC
Ret
urn
toM
aste
rTO
CR
etur
nto
Mas
ter
TOC
Wiring Diagram - Entire Machine - Codes 10151 - 10153 - (G2773)
NOTE: This diagram is for reference only. It may not be accurate for all machines covered by this manual. The wiring diagram specific to your code is pasted inside one of the enclosure panels of your machine.
G-3ELECTRICAL DIAGRAMS
INVERTEC STT & STT II
R
32A32B
1516
J22
R
B18V
32C
43A
R
U3
18V501
B
504
W45 5
2751863
311 10J6
1
212A97
212
352
212B503A
Y301305245223
81131
3 50324V
351
244
CASE
CASEBACK
PLATFORM
4 AMP
S
BOTTOM
S
OUTSIDEIY Y
4,5
12D
NO
O12
H3H1
FAN
SLOW
12B
RIGHT
MOTOR
BLOW
H1
1
J11
6 5
379
2
J9
CR2
H3
3 4
2W10KCW (MAX)
353
362
363
CONTROLBACKGROUND
2
1267410
3
ASSEMBLY
INPUT
LINE
POWERLINE
LOAD
N.L.
DC
B
A
F
S1POWER
OFFW
ON
UA
INPUTPER
R
N.A.V
B
BW
C
G
C
B
C
A
B
FILTER
A
52
TRIGGER
CORE
31756824
8
714
12C12D
- ARC
+ ARC
CURRENTMETER
VAC
12D
A
37811
363
J4
CW (MAX)
1 12 23 34 4565
359
358
2W10KR11
3
5
377
56
6TRANSFORMER D1O
374N
I
OT3 CURRENT
N2
5N.E.
4371 1
3
43
10
J5R
210
211A
502
246
212C
J3 6
B
Y
9
364365366
25
1 367
369368
WB
2
4
129
1
5
789
13
10
1
J281011
89
7
5
8
10
53
14
2
46
6
J332
3723724371
5
J1
67
J27
2376
R
1
1
4
370 370
376374
371B
3
8
12
115V
37410
132
2
33B87 33A
J26
B
3
E
R
BW
4
290A
110
367A
369
.045
502 (-)
INDICATOR
J25
115
223
357356
5
3556
354
6
21
CB2
J37
403
504
TRANSFORMER AUXILIARYT1
AUXILIARY
T4N.D.
TRANSFORMER
131 501
220-
212A
150 5W
4
0VH3
H2
H1H1
9A
9A
9D
9A
PROTECTION
13
9C
RW
S7RECONNECT
1
12B
12B
212C
287
43A
R18V
413
359
714
2
356
358
355354
357
352
1610
351
360
15
353
361
21
362
244303303
242
302
371A
302
374A
304304275
305
243
2301
4
240241
DARLINGTON
12
522
12D
24
W
1
D3
4
SF5
D4
1BOARD3
J16
TOPD5
57 DRIVER
F
12B
MOTOR FANLEFT
H1
MOTOR
TOP
H3
FAN
H1 H3
H1
D13RECTIFIER
TP2
TP1
-
TP3
9D
J16, J28
J34
A
N.K.413416
405
408
406
VAC
1
VAC
73
4321
F8
52
314315
J13
ELECTRODE SENSE LEAD
360
367
S2
VAC
368
367A
STAINLESS
R12
42
S3
.035
INTERFACE
503
TRIGGER
MILD
378
PEAK
377
PEAK
METERBACKGROUND
CONTROLHOT START
CW
WIRE TYPE
2W500K
TAILOUTCONTROL
R14
N.J.
REMOTE
15
407
2
6
63
115
350
J35
9
1211
6J17
J23J24
METER PINOUT (VIEWED FROM BACK OF METER)
ELECTRICAL SYMBOLS PER E1537
W
18V
N
J2
2
J23
Y
380-
4
415V
H3
1
H2H3230V
200-208V
N.M.
BACK
FOR SINGLE PHASE INPUT: CONNECT GREEN LEAD TO GROUND PER NATIONAL ELECTRIC CODE.
6V
10V
J24
18V
THERMOSTAT
COLOR CODE:
U
FAN
U
Y
WRAP RED LEAD WITH TAPE TO PROVIDE 600V. INSULATION.
J26
CONNECT BLACK & WHITE LEADS TO SUPPLY CIRCUIT.
B = BLACK CASE TRAYG = GREENN = BROWN
FRONT
NOTES:
O = ORANGER = REDW = WHITE
N.A.
J25
Y = YELLOWU = BLUE
1. FOR MACHINES SUPPLIED WITH INPUT CABLE
N.M. PRESENT ON EUROPEAN VERSIONS, CODE 10383 AND HIGHER.
FOR SINGLE PHASE INPUT: GROUND MACHINE PER NATIONAL AND LOCAL ELECTRICAL CODES.
CONNECT TERMINALS U, V & W TO SUPPLY CIRCUIT.
CONNECT TERMINALS U & W TO SUPPLY CIRCUIT.FOR THREE PHASE INPUT: GROUND MACHINE PER NATIONAL AND LOCAL ELECTRICAL CODES.
N.B. SINCE COMPONENTS OR CIRCUITRY OF A PRINTED CIRCUIT BOARD MAY CHANGE WITHOUT AFFECTING
COMPONENTS OR CIRCUITRY HAVING A COMMON CODE NUMBER.THE INTERCHANGEABILITY OF A COMPLETE BOARD, THIS DIAGRAM MAY NOT SHOW THE EXACT
CONNECTION SHOWN IS FOR 440-460V OPERATION.N.D. PLACE "A" LEAD ON APPROPRIATE CONNECTION FOR INPUT VOLTAGE.
N.E. D1 THRU D5 OUTPUT DIODES ARE A MATCHED SET.D7 THRU D11 OUTPUT DIODES ARE A MATCHED SET.
9
N.F. R1, R9 BLEEDER RESISTORS ARE A MATCHED SET.
J21
1 N.G. C1, C2 CAPACITORS ARE A MATCHED SET.
P21
2
PINOUT OF FRONT PANEL CONNECTORS (REAR VIEW)
3
4
3
5
J29. J31
2
CONNECTION SHOWN IS FOR 380-460V OPERATION.6 N.H. PLACE SWITCH IN APPROPRIATE POSITION FOR INPUT VOLTAGE.
1
6
N.I . DENOTES A TWISTED WIRE PAIR OR GROUP.
1
5
P29, P31
2
4
3
J30
43
52
61
P30
6
1
15
J22
9
FOR THREE PHASE INPUT: CONNECT GREEN LEAD TO GROUND PER NATIONAL ELECTRIC CODE.
2
24
3
2
N.K. NOT PRESENT ON EUROPEAN VERSIONS, CODE 10309 AND HIGHER.
4
1
105
3
11
4
612
N.L. PRESENT ON EUROPEAN VERSIONS, CODE 10309 AND HIGHER.
4
138
3
14
P22
158
16765
164
153
142
131
1211107
J38
J19
N.J. NOT PRESENT ON EUROPEAN VERSION.
2. FOR MACHINES NOT SUPPLIED WITH INPUT CABLECONNECT BLACK, RED & WHITE LEADS TO SUPPLY CIRCUIT.
J39
1 2 3 4
310309
310A310
309A
309A
310A
2
6
J7224A
102W
309
INSIDE
12B
25W
+2200 F
C1
-
BOARD
25450V
R4
(RIGHT)
3415
307
236
308
J1089D
4
5252
2 B
2
9
J34
J36
C42W R310 .001/400
N.E.
5W
12C 12A
S
FOUTSIDETOP
CHOKE
BOARD
3
12A
J12J8
14
N.H.
BOARD
224
R
310
J15
316
9B9B
12B401, 403
1, 8 8
371J22
5112B
12B
TOP
12B
.001/400
CR1
25 2200 F450V
9A
25W -
+
53
9A
+
N.G.9
R612A
R7
12A 12R W R W
401, 403
402, 404
(LEFT)BOARD
SWITCH
1, 8
25W25
4, 5
I
21
WIRE
8182
GND
424241
FEEDER
3231
J39
NBHLM
42
414
B
H1
+C
432
JA
812
TRANSFORMER
C8
288
4
2 300W289 R16
288A
SENSE
C2
L34
MAIN
13
289A
20/400
D11
T2
2J18 4
F S
4
313
3
32 J14
210A
210
THERMOSTATCHOKE
FANCASEBOTTOM
1
1
S
INSIDE
FBOTTOM
D9
BOTTOMD10
1
14
311
53
3
4
33C
N
J30
33
1
2 66
224
H6
H4
A
440-460VA
5
9
J3142V
H5
H4
115VJ21
R15
CE
2 300W
G
J38
409 A412 D404
CURRENT
F411
291
H GND
B
MODULEBR
DRIVEBOARD
14317
99B9B
402, 404+
N.G.N.F.R52525W25W
7500
R9
9B SWITCH
G3136
INLINE CONNECTOR CAVITY NUMBERING SEQUENCE(VIEWED FROM WIRE SIDE OF CONNECTOR)
DARLINGTON
EB
B402
W
401W
C
J
410 10K
PB10K
OPTIONAL
D
CB1
C
7675
6AMP
FG
43B42
9A
9D9C
345
BOARDPOWER
8309
7308307
W
14THERMOSTATWHEATSINK
J22503A
DARLINGTON
503B
242243
241
240
374A371A
11
211A
9
350
5
R125W7500
N.F.
D7D8
R2
12
W
D2
C3
35314
J10, J13,J15, J35
J3, J9,
J2, J36J4, J17
(VIEWED FROM COMPONENT SIDE OF BOARD)
J5, J7,
E
1
I
34
77
K
Y
R13
(+)
10K
2
2W
CW (MAX)
3
361
CONTROL
366
503A
WIRE SIZE
THERMALOVERLOAD
364
365
7
6
8
5
1613
15
14
412
11
CONTROL
CURRENT
BOARD
415
31A33D
6AMP
46
246
245
2122
SHROUD
212B32C33C
D12
313
J6, J27, J33J18, J37J11, J12, J14
P.C. BOARD CONNECTOR CAVITY NUMBERING SEQUENCE
J1, J8,
BG
SENSE
(-)
VOLTAGE
CONNECTION(+)21
J19
290
PROTECTION BOARDREMOTE
288B
TOROIDAL
289B
374
351H56
51
9B
N.L.
D-RW
G-3R
etur
nto
Sec
tion
TOC
Ret
urn
toS
ectio
nTO
CR
etur
nto
Sec
tion
TOC
Ret
urn
toS
ectio
nTO
C
Ret
urn
toM
aste
rTO
CR
etur
nto
Mas
ter
TOC
Ret
urn
toM
aste
rTO
CR
etur
nto
Mas
ter
TOC
Wiring Diagram - Entire Machine - Codes 10381 - 10383 - (G3136)
NOTE: This diagram is for reference only. It may not be accurate for all machines covered by this manual. The wiring diagram specific to your code is pasted inside one of the enclosure panels of your machine.
G-4ELECTRICAL DIAGRAMS
INVERTEC STT & STT II
G-4R
etur
nto
Sec
tion
TOC
Ret
urn
toS
ectio
nTO
CR
etur
nto
Sec
tion
TOC
Ret
urn
toS
ectio
nTO
C
Ret
urn
toM
aste
rTO
CR
etur
nto
Mas
ter
TOC
Ret
urn
toM
aste
rTO
CR
etur
nto
Mas
ter
TOC
Wiring Diagram - Entire Machine - Codes 11090 - 11092 - (G4500)
NOTE: This diagram is for reference only. It may not be accurate for all machines covered by this manual. The wiring diagram specific to your code is pasted inside one of the enclosure panels of your machine.
G-5ELECTRICAL DIAGRAMS
INVERTEC STT & STT II
+
-
ELECTRICAL SYMBOLS PER E1537
1 2
3 4
1 3
4 6
1
6 10
5
{
1 4
85
H1
T1
FANMOTOR
G
F
E
JA
I
KCD
M
L
B
N
H
75
76
77
3132
41
42
24
81
82
21GND
SPARE
42
VAC
T3CURRENT
TRANSFORMER
1
4
T2MAINTRANSFORMER
R3
OFFON
H1 TP1
TP3
TP2
I
I
5
8
D1
D2
D3
CHOKE
L3
CONTROLBOARD
10K2W
R11
307308309310
302303
304
POWERBOARD
(VIEWED FROM COMPONENT SIDE OF BOARD)
NOTES:
TRIGGER
}INPUTPERN.A.
POWER
S1
1}
2
3
1
78 }}J7
J6
CB1
504
43A
AUXILIARYTRANSFORMER
245613
N.E.
CW (MAX)
9
10
F
F S
S
S
TOPOUTSIDE
BOTTOMINSIDE
S
S
SF
F
TOP
TOPINSIDE
BOTTOMOUTSIDE
7
68
4
5
CONTROL
211A
212B
150 5W
FANTHERMOSTAT
H2
H3
H4
FBOTTOM
F
212A
W
V
U
H1
2120V
24V
42V
18V1
4
2
3
.001/400
COLOR CODE:
R = RED
6H5
2
3
6
4
7
8
5
502
Y
301
D4
D5
1 7
8 14
D11
D10
D9
D8
D7
N.E.
210
6AMP
H2
H3
H4A
9C
W
B
G
A
FOR THREE PHASE INPUT: CONNECT GREEN LEAD TO GROUND PER NATIONAL ELECTRIC CODE.CONNECT BLACK, RED & WHITE LEADS TO SUPPLY CIRCUIT.
WRAP RED LEAD WITH TAPE TO PROVIDE 600V. INSULATION.
FOR THREE PHASE INPUT: GROUND MACHINE PER NATIONAL AND LOCAL ELECTRICAL CODES.CONNECT TERMINALS U, V & W TO SUPPLY CIRCUIT.
CONNECT TERMINALS U & W TO SUPPLY CIRCUIT.
N.D. PLACE "A" LEAD ON APPROPRIATE CONNECTION FOR INPUT VOLTAGE.CONNECTION SHOWN IS FOR 380-415V OPERATION.
CONNECT BLACK & WHITE LEADS TO SUPPLY CIRCUIT.FOR SINGLE PHASE INPUT: CONNECT GREEN LEAD TO GROUND PER NATIONAL ELECTRIC CODE.
FOR SINGLE PHASE INPUT: GROUND MACHINE PER NATIONAL AND LOCAL ELECTRICAL CODES.
W = WHITE
B = BLACKG = GREEN
Y = YELLOW
H6
N.D.
R
H1
+ ARC
- ARC102W
C4
.001/400
9D
H1 H3
H3
415V
200-208V
380-
R2C3
102W
Y Y
305
1234} J14
311313
A
4 AMPSLOWBLOW
N.A.
N.B. SINCE COMPONENTS OR CIRCUITRY OF A PRINTED CIRCUIT BOARD MAY CHANGE WITHOUT AFFECTING
N.E. D1 THRU D5 OUTPUT DIODES ARE A MATCHED SET.
N.F. R1, R9 BLEEDER RESISTORS ARE A MATCHED SET.N.G. C1, C2 CAPACITORS ARE A MATCHED SET.N.H. PLACE SWITCH IN APPROPRIATE POSITION FOR INPUT VOLTAGE.
THE INTERCHANGEABILITY OF A COMPLETE BOARD, THIS DIAGRAM MAY NOT SHOW THE EXACTCOMPONENTS OR CIRCUITRY HAVING A COMMON CODE NUMBER.
D7 THRU D11 OUTPUT DIODES ARE A MATCHED SET.
CONNECTION SHOWN IS FOR 380-415V OPERATION.
12D
INPUTRECTIFIER
D13
10K2W
CW (MAX)
CONTROL
BACKGROUNDMETER
METER
1
}J2
11
8
10
4
9
3
2
7
13
126
14
5
BACKGROUND
BOARD
4
}
31
2
42
1
3
CURRENTSENSE
J1
J18 IGBT
MODULE
IGBTBOARDDRIVE
J13
GE
1
23
6
4
5
J12
J5
J3
910
1
2
34
56
1. FOR MACHINES SUPPLIED WITH INPUT CABLE
2. FOR MACHINES NOT SUPPLIED WITH INPUT CABLE
1234
VOLTAGESENSE
CONNECTION
J19
1
18V
18V
AUXILIARYTRANSFORMER
115V
10V
18VR
W
R
B
B
U
U
E C
D7
U = BLUE
212A
212
501504
T4
275
351350
352353354355356357358
358
359
359
360
360
361
361
362
362
363
363
290
291
J21
2
9
3
4
12
13
N
O
12
43
67
5
8
109
R12
J18, J37 J6, J27, J33
1 8
9 16
J19
1
4
2 3
J15, J35
210A224
20/400C8
287
288A
288B
289A
289B
364365366
368369
372
376
NO
O = ORANGEN = BROWN
123456
123456
354355
356357
10K2W
CW (MAX)
CONTROLHOT START
R13
WIRE SIZE
WIREFEEDER
CB2
BOARD
+
12
C1
R4
R52525W
2525W
9 5
8
+
12
2525W
2525W
9
C2
R6
R74
1R1
750025W
9A
308307
402, 404
401, 403
4,5
1, 8
R
R W R W
401, 4031, 8
4, 5402, 404
SWITCH+
-
+
-
SWITCH
DRIVERBOARD
416 3
J10
2 5
BOARD
1
23
4
52
14
51
53
14
J8
PROTECTION52
2200 F450V
N.G.
N.F.
N.G.
2200 F450V
(LEFT)
BOARD(RIGHT)
12B
9B9B
R9
9A
5312A
H5
750025W
52
1
2
34
5
6
314315
317
J15
N.F.
12A
12B
51
41 32
J11
73
21
8
12
13
14
}
J16
9D
3 6 4 1
J9
2 5
12B
12D
501
115V
11
10371 371A
374A374
J22
240
241
242
243
244
245
246
O
O
18V
6V
N
N
240241242
3
4
5
6
1213
714
1
2
8
9
1011
303302304275
371A374A243244 }
J27
1112
J4
374
370371
367
}
J28
}371374
1
}
}
234
1516
364
365
366
(+)
(-)
367
368
369
367A
367A
WIRE TYPESTAINLESS
MILD
JBCGADFHEI
TRIGGER
GND
}
.045.035
BG
PB
10K
10K
OPTIONALREMOTEINTERFACE
1 6
7 12
{
{115
VAC
3
2
5
4
1
U
W
R
R
Y
N
Y
2
1 32
33
32C
33C
32A
32B
33A33B
7
8
15
16
J22
2 • • 300W289
288
2 • • 300W
J33}223
7
J34}33C
1
2
3
4
5
643B
31A
}
J35
42
33D6AMP
J36
1234
}
J37
J30
J31
503A
R14
8
21
67
3
4
5
372
376374
370371
62371
8
54
109
61
584
32
J24 J23
J26 J25
353352
351350
123456
123456
42
VAC115
VAC
}J39
1
2
4
3
6
7
5
8
10
9
11
12}502
210
223
Y
305245
211A212C
Y
246
301
J17
}
503
503A
212C43A
212B32C
3
12
10912411
146
13
5
16
8
15
7
J38
503
REMOTEPROTECTION BOARD
S2
S3
(-)
(+)
THERMALOVERLOADINDICATOR
R13
J10, J13,J1, J8, J3, J9,
J5, J7,
J34
J2, J36
A
D
B
C
E
F
GH
I
J
J38
ADB
C
E
FG
HI
K
J39
L
MNJ
PINOUT OF FRONT PANEL CONNECTORS (REAR VIEW)
1 2
3 4
12
34
P30 J30
1 2 3
4 5
23
45 6
1
6
P29, P31 J29. J31
1 2 3
4 5
23
45 6
1
6
P21 J21
1 2 3
9 10
23
10 11
14 5 6 7 8
12 13 14 15 16
P22 J22
INLINE CONNECTOR CAVITY NUMBERING SEQUENCE(VIEWED FROM WIRE SIDE OF CONNECTOR)
45678
9111213141516
J23J24J25J26
P.C. BOARD CONNECTOR CAVITY NUMBERING SEQUENCE
METER PINOUT (VIEWED FROM BACK OF METER)
1 1
6 6
B
WWB
R
WB
BW
R
W
RB
B
PEAKCURRENT
PEAKCURRENT
B
WB
R
N.I. DENOTES A TWISTED WIRE PAIR OR GROUP.
N.J.
RW W
52
316
31131314
309
310CR1
9A
9A
9A
9A
53
9D
N.H.
9C
12C
9B
12A9B
12A
9B
S7RECONNECT
9D
12C
12D
309A
310A
309310
CR2 309A
310A
12D
52
9B
12B51
12B
12B12B 12B
12B
14
6224
503A
224A
J22 THERMOSTAT
DARLINGTONHEATSINK
W
W
C
B
A
C
B
A
D
F
C
B
A
503B
J11, J12, J14
J4, J17 J16, J28
401402403
404
405
406
407
408
409410
411
412
413
414
415
416
C
B
A
C
B
A
LOAD
LINE
POWER LINEFILTER
ASSEMBLY
N.L.
N.K.
N.K. NOT PRESENT ON EUROPEAN VERSIONS.N.L. PRESENT ON EUROPEAN VERSIONS.
N.J. NOT PRESENT ON EUROPEAN VERSIONS.
TOROIDALCORE
N.L.
}
G4557 A
G-5R
etur
nto
Sec
tion
TOC
Ret
urn
toS
ectio
nTO
CR
etur
nto
Sec
tion
TOC
Ret
urn
toS
ectio
nTO
C
Ret
urn
toM
aste
rTO
CR
etur
nto
Mas
ter
TOC
Ret
urn
toM
aste
rTO
CR
etur
nto
Mas
ter
TOC
Wiring Diagram - Entire Machine - Codes 11115 - 11116 - (G4557)
NOTE: This diagram is for reference only. It may not be accurate for all machines covered by this manual. The wiring diagram specific to your code is pasted inside one of the enclosure panels of your machine.
G-6ELECTRICAL DIAGRAMS
INVERTEC STT & STT II
J2811
50V0.1C413
+15V_REM
50V0.1C411
+15V_REMREM
REM
3.92
K
R46
3
METER_2
METER_1
PB_SCALED
1.00
K
R43
6
3.92
K
R461
J2810
J286
J283
15.0K
R437
10.0K
R431
OCI4
Vcc
GND
HP2231
5
8
1.00
K
R43
2
0 .01
W4
FILE: G2781_1D1
+PWR
+VIN
-PWR
+VIN
+PWR
BA
CK
GR
OU
ND
MET
ER
-V IN
POWERTO
BOARD
4
2
3
J1
1 Input- CurrentFeedback
Vac InCOMMON CONNECTION
FRAME CONNECTION
LAST NO. USED
129, 211, 314, 475
165, 242, 345, 564
117, 211, 310, 424
VOLTAGE NET
1
9 16
8
to Control Panel
Analog Logic I/O
J2
to Control Panel
Analog Logic I/O1
6
3
4
J3
C-
D-
R-
SUPPLY
LABELS1/4W(UNLESS OTHERWISE SPECIFIED)
UNLESS OTHERWISE SPECIFIED)
200 SERIES- TRIGGER CIRCUIT100 SERIES- ARC SENSE CIRCUIT
REFERENCE DESIGNATOR SERIES DEFINITIONS
GENERAL INFORMATION
1A, 400VRESISTORS = Ohms (
MFDCAPACITORS =ELECTRICAL SYMBOLS PER E1537
DIODES =
( .022/50V
(SHEET 2)
UNLESS OTHERWISE SPECIFIED)
(SHEET 2)
+15V
COMM
PHA OUTPUT
PHB OUTPUT
0.01 W
1
ON HOLES SIZES PER E-2056ON 2 PLACE DECIMALS IS + .O2
UNLESS OTHERWISE SPECIFIED TOLERANCE
3SEC
ARC_START
WITH PUBLISHED STANDARDS
ON 3 PLACE DECIMALS IS + .OO2ON ALL ANGLES IS + .5 OF A DEGREEMATERIAL TOLERANCE ("t") TO AGREE
J36
Ch'ge.Sht.No.
+5.1V
PLA
SM
AB
OO
ST
MET
ER
-PWR
-VIN
A
J2813
J285
3920V
C469
562
R47
9
Q62N4401
J274
J2812
33.2K
R485X18 3
2
1
J278
J289
J284
J282
J35
X22
3
5
4
RemoteControl106
51
J27
J28
14
1 7
8
Dar l ingtonDrive- Output
W4
STT CONTROL
Q10
POWER SUPPLY SOURCE POINT
SCHEMATIC (Sheet 1 of 2)
DZ20
EARTH GROUND CONNECTION
OCI7
SHT.NO. G
X36
SUP'S'D'G.04/12/94SCALE
DATE
NONECLEVELAND, OHIO U.S.A.
DR. MLD
300 SERIES- DIGITAL LOGIC CIRCUIT400 SERIES- ANALOG LOGIC CIRCUIT
THE LINCOLN ELECTRIC CO.
SUBJECT
CHK.
EQUIP.
(SHEET 1)
TYPE
(SHEET 1)
ANAND
B
HO
TS
TAR
TTI
ME
CW
10K
N.A. S INCE COMPONENTS OR CIRCUITRY ON A PRINTED CIRCUIT BOARD MAY CHANGE
NUMBER.
WITHOUT AFFECTING THE INTERCHANGEABILITY OF A COMPLETE BOARD, THIS DIAGRAM MAY
NOTES :
NOT SHOW THE EXACT COMPONENTS OR CIRCUITRY OF CONTROLS HAVING A COMMON CODE
PINCH SLOW RAMP
COMMAND SIGNAL
BALL
PINCH KNEE
KEEP_ALIVE LEVEL
PINCH FAST RAMP
BACKGND
P_BOOSTPINCH RAIL
RAMP
FUSE
KEEP_ALIVE LEVEL
TAILOUTBACKGND
OFF
J273
C453
100K
R496
X30
3
5
4
10.0K
R536100
R481
MILD
-> .045 DIA WIRE
< .035 DIA WIRE-
CURRENT FEEDBACK
1V/100A
WIRE TYPE SELECT
WIRE SIZE SELECT
SENSEBOARD
1014B
5V3V
BNAND
+15V POWER SUPPLY FORDIGITAL, TRIGGER & ANALOG SECTIONS
10K
CW
REM
OTE
PB
PO
T
STAINLESS
18 VAC
lm350
A1014
INTEGRATORCURRENT
CURRENT
COUNTERDUAL FFPWM
G
POWER PLANE
COUNTER
GROUND PLANE
33.2
K
R518
X351
2
3
1.035V
C423
X36 45
6
332K
R522
X357
6
5
68.1
K
R514
221K
R521
10.0K
R510
68.1K
R513
J271
200V.33
C46447.5K
R5191W10V
DZ9
J11
J12
1.035V
C412+ t56
R526
J31
J14
J13
10.0
R466+ t.25
R4671 2
J34
X25
SG3846
12
13
1W10V
DZ20
1N914
D412
2.5V
LOC
AL
PB
PO
T
10K
CW
POWERPOTS
CONTROL10 VDC
REMOTE_POTS
+15V
+15V
C461
2.67K
R544
75.0
R504
100
R489
10.0
R50
0
100
R50
7
J272
J279
J2710
J33
X33
TL431 REF8
1
6
SS_WIRE
1.035V
C404
2.67K
R545
5.62
K
R47
2
1.30
K
R50
5
1 .035V
C402
2.67K
R406
1W12V
DZ11
1.0 35V
C446
1.035V
C460
1.00
M
R46
9
1 .0
35V
C400
C401
1.50
KR
503
D407
J215
100
R404
+15V
1W12VDZ10
1.30
K
R40
0
1.30
K
R401
J32
J216
J210
75.0
R40
2
1.30
K
R50
6
D400
C403
10.0
R501
1.00
MR
533
1W12V
DZ18
10.0K
R403
4.75
KR
502
2 .67K
R546
/PB_LOCAL
NAND
+15V
Q92N4401
/ARC
X14 11
12
13
X14 108
9 10K
R320
OCI1
HP2231
1
2
LT1014
X24
4
11
4066B
X30
14
7
LM2901
X23
3
12
50V0.1
C459
1N4936D303
50V0.1
C427
100V330pC306
+15V
/PINCH
/PWM_SYNC
/PWM_SYNC
NAND
14
7
/Q2
D1
VDDQ1
SET 2
CLOCK 2
/Q1 Q2
CLOCK 1
VSS
RESET 1
MC14013B
SET 1 D2
RESET 2
X19
11
10
13
8
12
2
1
6
4
9
5
3
50V0.1
C428
3.92K
R457
X17 45
6
X14 32
1
B
2.21
K
R317
100V
330p
C305
OCI3
HP2231
6
3.01
K
R45
6
3.01
K
R45
4
56.2
K
R321
4 .75K
R319
OCI3
HP2231
7
4.75K
R318
X16 45
6
+15V
ARC_START
/PWM_SYNC
START_RESET
NAND
D
PINCH SIGNALTO FE (SHEET 2)FOR ENERGYCONTROL OPTION
"DIGITAL LOGIC"
GROUND PLANE
C
A
BALL_OR_FUSE
NAND
OP AMP
B
A
NAND B
NAND
POWER PLANE
COMPARATORSWITCH
ENABLE (SHEET 2)ENERGY CONTROL OPTION
PINCH LATCH
P_BOOST ONLY AFTER
P_BOOST TIME (SHEET 2)ENERGY CONTROL OPTION
H = A>100V=ARC
KEEP IN P_BOOST
UNTIL ARC STARTS
CX16 10
8
9
150K
R422
SLOW RAMP
Q82N4401
2.67
KR
452
3 .32K
R426
13
12Vc
GND
SYNC
X25
V+ Vref
CLIM
OUTBCOMP
I-
I+
V-
OUTA
SHUT
CT
RT
Vin
SG38469
3
8
4
10
5
6
2
15
11
14
16
1
7
B
P_BOOST COMMAND
C473
L= .035H= .045
( SHEET 2 )
Verror
X22
8
6
9
10.0
K
R551
100
R405
1us MIN PULSEWIDTH
15.0K
R453
3us MAX DEADTIME
10KCW
R425
1N4936
D401
500
CW
R42
9
267K
R42
3
1 .00K
R427
47.5K
R419
100K
R424
100A/ms
A
RAMPPINCH
1014
X21
10
12
11
1.00K
R428
X24 1
2
3
100V47p
C410
475K
R421
47.5K
R420
100K
R416
X21
8
6
9
X31
10
12
11
100K
R55
2
X21
1
13
2
3920V
C465
15.0K
R410
B 1000A/ms
FAST RAMP
50V.018C418
10.0
KR
564
CURRENTERROR AMP
22.1
KR
555
GENERATOR
WAVEFORM
SAWTOOTH
1.820V
C419
D
Q42N4401
B
COMMAND
6.81K
R411
A
100V100pC472
Q102N4401
47.5K
R409
COMMAND
LOCAL_POTS
26.7
KR4
51
+15V
+5.1V
LOCAL +15V
NAND
MC14538BTIMERTIMER OP AMP
GROUND PLANE
ALM224
375us
+5 VOLT
POWERMETER
2.5V
BLM224
POWER PLANE
2.67K
R508
825
R48
6
10.0K
R527
X34 7
6
5
X26
TL431 REF8
1
6
1.035V
C448
1.00
MR5
11
D413
C314
X34 1
2
3
C463
10.0K
R528
1W12V
DZ19
825
R48
8
825
R48
2
825
R48
72.
21K
R47
3
2.43
K
R47
4
10.0
R484
10.0
R483
1.035V
C462
4093B
X11
7
14
50V0.1
C433
50V0.1
C432
50V0.1
C467
50V0.1
C466
LT1014
X35
4
11
4093B
X12
7
14
X9
16
8
MC14538B
X10
16
8
50V0.1
C445
LM224
X34
4
11
50V0.1
C443
50K CWR301
3.92
K
R30
0
4 .735V
C440
+15V
+15V
J2814
50V0.1
C439
50V0.1
C442
50V0.1
C456
50V0.1
C441
MC14040
X32
8
16
MC14040
X20
8
16
1N4007D307
1400V.0047C310 243
R337
100035VC311
C312
1N4007D308
J287
2.67K
R541
500
CWR33
9
2 .67K
R543
2.43
KR
338
2 .67K
R542
10020V
C313
MC14013B
X19
7
14
1N4007D306
1N4007D309
ADJ
IN OUTs18395-23
X8
D310
15.0
K
R33
5
15.0
R515
X23 1
6
7
100K
R45
0
OCI6
HP2231
1
2
X22
1
13
2
1N4936
D302
1N914
D424
X31
3
5
410.0K
R444
82.5
K
R56
0
X36 108
9
X36 1112
134.75K
R537
100
R525
D402100V
330pC471
D410
150K
R52
3
PRI_FB
PB_START
+15V
+15V
+15V
ARC
+15V
PINCH
CFB
+15V
PINCH PWM_EN
1014 B
BCNAND
1014
CO
MM
AN
D
ARC
&/R
AMP
CTR
L
A
PB_START SIGNALTO FE (SHEET 2)FOR ENERGYCONTROL OPTION
( SHEET 2 )
A
1014
OVERCURRENTTRIP TIMING
X30
1
13
2
LOCAL
56.2
K
R30
7
P BOOST
X21
3
5
4
X247
6
5
10K
.294V
C1014
PIN
CH
FAST
RAM
PEN
ABLE
2901C
PINCH LIMIT
500A MAX
PIN
CH
BREA
KPO
INT
(PIN
CHKN
EE)
D
PINCH COMMAND
2901
B.PT
PIN
CH
CO
MM
AND
LM224C
B
LM224
"ANALOG LOGIC"
D
17.8
K
R40
8
X34 8
9
10
8.25K
R530
15.0K
R550
1.00K
R532
X2313
10
11
15.0K
R407
10K
R414
X2314
8
9
10KR412
50V
.0047C407
X248
9
10200
R413
/HOT_START
LOCAL_POTS
PB_SCALED
X34 14
13
12
2.21
KR4
17
2.21
K
R418
1 .035V
C409
1W15VDZ12
100K
R471
47.5K
R415
OCI2
HP2231
7
4093B
X13
7
14
10.0K
R540RST
/Q
T2QA
B
T1
X9
1
3
4
2
6
5 7
4.75K
R302
GROUND PLANE
POWER PLANE
NANDNANDOP AMP
FROM FE (SHEET 2)ARC/SHORT DETECT
C300
AARC
+15V
/BALL
PINCH
METER_1
METER_2
+15V+15V
REMOTE
PWM_EN
RAMP
+5.1V
P BOOST
OUTA
+15V
OUTB
10.0K
R539
0.01
W2
10.0K
R529
1.00
MR
448
100K
R45
9
0.01
W3
OCI4
HP2231
7
OCI4
HP2231
6
OCI5
HP2231
4
3
100V330p
C470
10K C
W
R441
X29 8
9
10
50V.0047
C422
26.7
K
R53
8
50V.0047
C41456.2
K
R44
2
OCI5
HP2231
1
2
D419
100K
R44
6
X22
10
12
11
22.1
KR
499
475
R45
8
100
R44
0
50V820pC416
D418
D404
13.7
K
R44
7
4 .75KR468
C415
D417
6.81
K
R49
4
RST
/Q
T2QA
B
T1
X10
1
3
4
2
6
5 7
OCI4
HP2231
4
3
OCI4
HP2231
1
2
/ARC +15V
+15V
/RAMPRAMP
START_RESET
/AR
CO
RR
AMP
CTR
L
CLM224
RAMP INP BOOST
120us
B
A
B
A
A
+1.42V
D
CURRENT LEVEL"KEEP ALIVE"
SCALED_BGND
PWM OUTPUTTO FRONT END
( SHEET 2 )
CIRCUITISOLATED
A
B
(SHEET 2)
332
R430
15.0
KR
439
D405
B
DARLINGTON
/DON_MIN
150us MIN
ON TIME
COUNTER
NANDNAND
DON_MIN
/CO
UN
T
3.92
K
X15 32
1
X15 45
6
A
16
8
VDD
/C
Q7
Q12
MC14040
Q4
VSS
RQ3
Q11
Q8
Q10
Q9
Q6
Q2
Q5
Q1
X2013
12
14
11
10
9
15
7
6
5
4
3
1
2
X15
1112
13
X16 32
1
4.75K
R557
A
50V0.1
C307
RST
/Q
T2QA
B
T1
X10
15
13
12
14
10
11 9
1N4936D421
511
R32
6
B
1N4936
D30110.0K
R325
10.0
K
R331
1 .00K
R345
DISABLE OPTION TO START
NAND
H= OPTION ENABLEDL= NO OPTION
4.75K
R323
1N4936D422
4.75K
R322
1N4936
D420
15.0
K
R341
LM224
X29
4
11
A
BOOST TIME LIMIT
50V0.1
C458
1.3 msec PLASMA
NANDPWM_SYNC
D
OP AMP
/PB_OPTION
+15V
PINCH
PB_START
+15V +15V
C
ANAND
R32
9
10.0K
R324
1.035V
C309
50V0.1
C308
/HOT_START
ARC_START
+15V
H= OPTION PB TIMEL= LOCAL PB TIME
X31
1
13
2
3.92
K
R33
2
X15 10
8
9
OCI2
Vcc
GND
HP2231
5
8
50V0.1
C429
10K
R312
50V0.1
C425
4066B
X31
14
7
10K
R455
/RESET
CFB
RESET
+5.1V
OUTA OUTB
50V0.1
C426
X12 108
9
SWITCHSWITCH
X14
45
6
10KR316
39.2
K
R311
10.0K
R310
BAL
L_O
R_F
USE
PWM
2901B
1V=100A
DNAND
NAND
CNAND
3.1V
1014D
1V
RST
/Q
T2QA
B
T1
X9
15
13
12
14
10
11 9
24.3
KR
553
C47
4
100K
CWR313
X3514
13
12
X17
108
9
15.0KR554
C304
4066B
X22
14
7
50V0.1
C457
CFB
/PINCH
+5.1V
+15V
+15V
33.2
K
R517
OVERCURRENT TRIP
33.2
K
R516
X35 8
9
10
+15V
+15V
FUSE
+15V
50V0.1
C438
DV/DT
NAND
FROM FE (SHEET 2)DV/DT LEVEL DETECT
4093B
X18
7
14
4093B
X14
7
14
D
4066B
X21
14
7
4093B
X36
7
14
X11 45
6
X1611
12
13
D305
OCI1
HP2231
4
3
50V0.1
C468
D300FUSE
+15V
PINCH
ARC
+15V +15V
NAND
FUSE GEN.
DV/DT
1ms
B
REPETITIOUSPINCH LIMITER
COUNTER
FORCES THIRD CONSECUTIVE
PINCH TO BREAK INTO ARC
DV/DT KILLER
/KIL
LER
NANDSWITCH
NAND NANDNANDNAND
BALL
A/KILLER
KILL_RC
CNAND
PINCH KILLER VarcADJUST FE (SHEET 2)
DNAND
D
/KIL
LER
NANDKILLER
KILL_START
B
750us
/KILLER
BALL_OR_FUSE
B
DNAND
3.92
KR
308
4 .75K
R340OCI2
HP2231
6
50V0.1
C434
50V0.1
C435
50V0.1
C436
50V0.1
C444
50V0.1
C437
4093B
X17
7
14
4093B
X16
7
14
4093B
X15
7
14
16
8
VDD
/C
Q7
Q12
MC14040
Q4
VSS
RQ3
Q11
Q8
Q10
Q9
Q6
Q2
Q5
Q1
X3213
12
14
11
10
9
15
7
6
5
4
3
1
2
X171112
13
C302
X1332
1
Q32N4401
X11 108
9
10.0K
R333
4.75KR305
100K
CW
R30
4
33.2
K
R30
9
X13 45
6
100V
330p
C303 10K
R314
Q72N4403
75.0
R512 X13 11
12
13
4.75K
R334
X11 1112
13
50V2700pC475
4.75K
R306
332KR562
10.0
K
R561
X12 45
6X12 11
12
13
5.62K
R303
100V100pC301
X36 32
1
D411
X12 3
2
1
10.0K
R509
10.0
K
R56
3
1N914D423
X11 32
1
X28 13
10
11
150K
R524 100KR559
12VdcCR1
C
/RESET
/ARC
PINCH
+15V
/BALL
/PINCH
ARC
/RESET+15V
+5.1V+15V
+15V
FUSESTART
FUSE_RESET
CNAND
B
ANAND
B
AMPS>100
A
NAND/ARC NAND
NANDA
BALL_DELAYED
OUTPUT DISABLEOVERCURRENT B
/BALL_DELAYED /(BALL & SHORT)
OVERCURRENT FAULT
( SHEET 2 )
TO TRIGGER CIRCUIT
ARC
B
RESETPULSENAND
/BALL_RC
CNAND
/KILLER
D2901 NAND
/ARCNAND A
/RESET
ANAND
150us FUSE ENTRY
ARC KILLER PULSE
1N4936D416
X17 32
1
X13 108
9
ARC
/RAMP
+15V
CW
SHORT OR 500K POT
500KTAIL OUT
A
BACKGROUND COMMAND
DNAND
D
INCREASE TAILOUT
DURING HOT START
C
LOC
AL
BG
PO
T
10.0
R434
J211
J214
82.5KR443C406
J25
J27
267K
R490
10.0K
R435
D414X31
8
6
9
1.00M R44
9
10.0K
R445
50V0.1C450
50V2700pC417
D409
X24
14
13
12
D403
REMOTE_POTS
X29 7
6
5
/HOT_START+15V
+15V
HOT_START
REMOTE
+15V
ARC_START
1.035V
C447 D408 HOT_START
REMOTE
LOCAL
DURING HOT START
11% BACKGROUND INCREASE
LM224
Unused Devices
D
C
LM224
TIMINGHOT START
GENERATOR
D
REM
OTE
BG
PO
T
CW
CW
10K
LM224
B
J275
J23
100
R491
J277
2.67K
R547
2.67K
R549
10.0
R492
2.67K
R548
100
R493
J276
1.00
MR
534
2 .67K
R495
X29 1
2
3
20.0K
R498
150K
R497
1.00
M
R52
0
D415
1W12V
DZ16
X30
8
6
9
X30
10
12
11
C455
C454
100K
R48
0
+15V
1.00
MR
476
D406
1W12V
DZ1510.0K
R478
1W12V
DZ17
1.035V
C452
X2914
13
12
1.035V
C451
100
R47
7
10.0
K
R47
5
C449
C405
+15V
J21
4.75
K
R55
6
X232
4
5
10KCWR328
Q2
2N4401
100
R34
2
10.0
KR
330
511
R32
7
J281
D304
X18 1112
13
J288
2.21
KR
343
100
R470
J24
50V0.1
C424OCI3
Vcc
GND
HP2231
5
8
+15V
/PB_OPTION
/PB_LOCALP BOOST
SS_WIRE
+15V
ON
OPTO
H = STAINLESS
L = MILD
C
L=DISABLE LOCAL PB TIME
ISOLATOR
BOARD
DO
N_R
ESET
B
2901
H= OPTION PB TIME
1W15VDZ8
2.21
KR
344
TO FE (SHEET 2)FOR ENERGY CONTROLOPTION
WIRE TYPE POSITION
X18 108
9
+5.1V
L=O
PTIO
NPB
TIM
E
D
L=DISABLE OPTION PB TIME
B
DARL. DRIVE
OCI6
HP2231
4
3
100
R433
50V0.1
C430
X18 45
6
J26
J212
J28
J29
J213
J22
5-19-95
5-24-96E
2781-A
2781-A
G-6R
etur
nto
Sec
tion
TOC
Ret
urn
toS
ectio
nTO
CR
etur
nto
Sec
tion
TOC
Ret
urn
toS
ectio
nTO
C
Ret
urn
toM
aste
rTO
CR
etur
nto
Mas
ter
TOC
Ret
urn
toM
aste
rTO
CR
etur
nto
Mas
ter
TOC
Schematic - Control PC Board - Codes 10151 - 11092 - (G2781 Sheet 1 of 2)
NOTE: Lincoln Electric assumes no responsibility for liablilities resulting from board level troubleshooting. PC Board repairs will invalidate your factory warranty. Individual Printed Circuit Board Components are not available from Lincoln Electric. This information is providedfor reference only. Lincoln Electric discourages board level troubleshooting and repair since it may compromise the quality of the design and may result in danger to the Machine Operator or Technician. Improper PC board repairs could result in damage to the machine.
G-7ELECTRICAL DIAGRAMS
INVERTEC STT & STT II
G-7R
etur
nto
Sec
tion
TOC
Ret
urn
toS
ectio
nTO
CR
etur
nto
Sec
tion
TOC
Ret
urn
toS
ectio
nTO
C
Ret
urn
toM
aste
rTO
CR
etur
nto
Mas
ter
TOC
Ret
urn
toM
aste
rTO
CR
etur
nto
Mas
ter
TOC
Schematic - Control PC Board - Codes 10151 - 11092 - (G2781 Sheet 2 of 2)
NOTE: Lincoln Electric assumes no responsibility for liablilities resulting from board level troubleshooting. PC Board repairs will invalidate your factory warranty. Individual Printed Circuit Board Components are not available from Lincoln Electric. This information is providedfor reference only. Lincoln Electric discourages board level troubleshooting and repair since it may compromise the quality of the design and may result in danger to the Machine Operator or Technician. Improper PC board repairs could result in damage to the machine.
OCI2
HP2231
4
3
47.5K
R211 X28 2
4
5
J43
X281
6
7
1N4936
D2001.00K
R200
J48
26.7
R20
6
47.5
K
R231
10.0
R23
0
CNY17-3OCI7
42
1
6
5
1.30K
R220
+ t60V.13
R239
2.21K
R216
J42
1W43VDZ4
CR1
11
9
13
1.30K
R218
1.30K
R217
( SHEET 1 )
PWM ENABLE
OCI2
HP2231
1
2
TO DIGITAL LOGIC( SHEET 1 )
DV/DT LEVEL DETECT
( SHEET 1 )
( SHEET 1 )
PINCH KILLERVarc ADJUST
ARC/SHORT DETECTTO DIGITAL LOGIC
Y
CURRENTTRANS.
Y
BOARD
OVERVOLTAGE
ON POWER
TRIGGEROPTOCOUPLER
FEEDBACK 125:1 RATIOPRIMARY CURRENT
CIRCUITTRIGGER
TSTAT
24 VAC
TSTATCHOKE
BOARD
OPTOCOUPLERSON PROTECTION
T1 AUX XFMR
OVERHEAT INDICATOR
150
FAN
R
5W
FAN
Y FROM SHEET 1OVERCURRENT FAULT
1N4936
D20522.1K
R210
C203
J46
J410
TO ANALOG LOGIC
TRIGGERINTERFACE
( SHEET 1 )
J411
1.30K
R219
J412
1.30K
R221
J45
1W43V
DZ5
1.30K
R224
1.30K
R223
4093B
X6
7
14
1N4007
D108
J58
C112
500
CWR158
X414
13
12
1N4007D109
J5
2735V
C119
243
R157
1.82K
R156100035VC111
J176
50V0.1C125
D107
SMP04
X3
Dgnd Vss
Vdd
8
16
13
50V0.1C121
2735V
C117
J1712
1400V.0047C113
J54
D114C120
OP470
X4
V+
V-
4
11
50V0.1C124
ADJ
IN OUT
s15128-15k1
X1
D112
OUTIN
GND
X2
s15128-12
D113
4735V
C115
C116
J1711
1400V.0047C114
1N4007D110
1N4007D111
J175
+12VFE
+12VFE
FE
+12VFE
FE
X6 45
650V0.1
C126
OCI6
HP2231
6
X48
9
10
+12VFE
-15VFE
COMPARATOR
FEFE
50V0.1
C128
50V0.1
C127
OCI6
Vcc
GND
HP2231
5
8
50V0.1
C122 OCI1
Vcc
GND
HP2231
5
8
50V0.1
C129
LM2901
X5
3
12
50V0.1
C123
C118
+12V OUT
XFMR
18 VAC
18 VAC
CT
36 VAC
COMMON OUT
-15V OUT
OP AMP7915
A
Energy Tr igger Circuit
I /O and VacOption
J5
1
85
4 Front EndVac and Varc 7
6
12
1
J4
7
6
12
1
J17
Control
ENERGYCONTROLOPTION
NEG FE POWER NET
DOP470
POWER SUPPLY FOR "FRONT END"
H = STAINLESS
L = MILD STEELB
UNUSED GATES
COP470
NANDC
POS FE POWER PLANE
OCI5
Vcc
GND
HP2231
5
8
J173
+12VFE
FE
ISOLATED CIRCUIT
LM350
NAND
POS FE POWER PLANE
FE GROUND PLANE
SENSE PANEL
ENERGY CONTROL
PHASE B
G
FRONT END
+ STUD
INPUT FROM
- STUD
VOLTAGE
H = START PLASMA BOOST TIMING
L = NOT PLASMA BOOSTOCI6
HP2231
7
OCI1
HP2231
7J171
THE LINCOLN ELECTRIC CO.
ENERGY CONTROL OPTION
WITH PUBLISHED STANDARDS
Ch'ge.Sht.No.
SCALE
DATE
NONE
EARTH GROUND CONNECTION
Q10
OCI7
LABELSX36129, 211, 314, 475
D-
165, 242, 345, 564
LAST NO. USED
C-
R-
SUPPLY
POWER SUPPLY SOURCE POINT
COMMON CONNECTION
VOLTAGE NET
FRAME CONNECTION
NOTES :
NOT SHOW THE EXACT COMPONENTS OR CIRCUITRY OF CONTROLS HAVING A COMMON CODE
N.A. S INCE COMPONENTS OR CIRCUITRY ON A PRINTED CIRCUIT BOARD MAY CHANGE
NUMBER.
WITHOUT AFFECTING THE INTERCHANGEABILITY OF A COMPLETE BOARD, THIS DIAGRAM MAY
DZ20
117, 211, 310, 424
( SHEET 1 )
ENERGY CONTROL
PINCH SIGNAL FOR
OPTION ENABLE
ENERGY CONTROLOPTION P BOOSTTIME ( SHEET 1 )
-15VFE
FE
-15VFE
WIRE TYPE POSITION
CLEVELAND, OHIO U.S.A. SUBJECT
TYPE
G
STT CONTROL
NO.SHT.
04/04/94MLD CHK.DR. SUP'S'D'G.
200 SERIES- TRIGGER CIRCUIT (SHEET 2)
400 SERIES- ANALOG LOGIC CIRCUIT (SHEET 1)
ELECTRICAL SYMBOLS PER E1537UNLESS OTHERWISE SPECIFIED)
300 SERIES- DIGITAL LOGIC CIRCUIT (SHEET 1)
EQUIP.
DIODES =
+ t56
R238
CAPACITORS =
1A, 400V (UNLESS OTHERWISE SPECIFIED)
100 SERIES- ARC SENSE CIRCUIT (SHEET 2)
REFERENCE DESIGNATOR SERIES DEFINIT IONS
MATERIAL TOLERANCE ("t") TO AGREEON ALL ANGLES IS + .5 OF A DEGREE
UNLESS OTHERWISE SPECIFIED TOLERANCE
ON 2 PLACE DECIMALS IS + .O2ON HOLES SIZES PER E-2056
ON 3 PLACE DECIMALS IS + .OO2
MFDRESISTORS = Ohms (
.022/50V1/4W
GENERAL INFORMATION
SCHEMATIC (Sheet 2 of 2)
(UNLESS OTHERWISE SPECIFIED)
W4
ENERGY CONTROL OPTION( SHEET 1 )
UNUSED
TO POWER ISOLATED CIRCUITBOARD
TRIGGER
C D
ON SHEET 1X28 "D" COMPARITOR
COMPARATOR
FILE: G2781_1D1
PB_START SIGNAL FOR
ENERGY CONTROL OPTION( SHEET 1 )
( SHEET 1 )
+15V
J44
J41
J49
LM2901
X28
3
12
J47
50V0.1C211
100V100p
C105
1N91
4D1
16X5 14
8
9
10K
R142
X3
SMP04
17
5
50V820pC110
825
R165
3 .92KR164
22.1
K
R132
X3
SMP04
1410
12
SMP_
STR
OB
E
13.7K
R122
+12VFE
+12VFE
FE
C
OLD DV/DTVarc SAMPLE
SHORT DETECTVarc SAMPLE
D
H=LOW DV/DTL=HIGH DV/DT
DV/DT 10XAMPLIFIER
ARCDETECTOR
A
2
2901A
ARC
ARC
_TRI
P
OP470B DV/DT 22901dv/dt
B
B
DV/DT SAMPLE PULSE
D2901
10K
R148
10K
R145
100K
R143
J174
68.1
KR1
27
1 .00M
R124
X52
4
5
X4 7
6
5
100K
R144
X5 13
10
11
8.25
K
R146
68.1
KR1
23
47.5
KR1
14
100V100pC103
51.1
K
R126
10K
R147
1N914D117
4.75K
R128
50V820pC109
X3
SMP04
159
11
1N914D102
4.75
K
R125
267K
R135
13.7K
R116
13.7K
R118
1N4007D100
26.7
K
R129
13.7K
R120
50V.0047
C104
20.0
K
R162
1W12V
DZ2
20.0
K
R108
DT
J178
X6 1112
13
1N4936D105
1N4936D106
J179
1.50K
R155
OCI5
HP2231
6
100V330pC106 X6 10
8
9
OCI3
HP2231
4
3
J177
OCI3
HP2231
1
2
681
R151
J172
1.50K
R161
332
R149
1 .50K
R160
X6 32
1
4.75
K
R136 1N914
D115
1.00K
R134 3.92KR163
47.5K
R133
3.92
K
R130
1 .50K
R154
OCI5
HP2231
7
3.92
K
R131
1N914D103
5KC
W
R150
1N914
D104
OCI1
HP2231
6
3.92
K
R152
Q12N4401
3.92KR153
X5 1
6
7
1W15V
DZ3
FE
FE
+12VFE
NEG_CLAMP
FE
FE
DT_
DEL
AYED
OU
T
B2901
A
C
DT_DELAYED D
DT_RC
OPTION ENABLE
PHASE A
OPTION P BOOSTTIME
ENERGY CONTROL DIODE ON = OPTION P_BOOST TIME
DIODE OFF = LOCAL P_BOOST TIMEOR NOT OPTIONP_BOOST TIME
B
AL = NOT PINCH
H = PINCH
ADIODE ON = OPTION ENABLED
DIODE OFF = OPTION DISABLED
1.89V NORMAL2.3V PINCH START
FOR INITIAL
ARC DETECTOR
PINCH PULSE
ADJUSTMENT
H=SHORTL=ARC
B
PWMFROM
FROMPWM
DT
DT
ATRUNCATES DT_DELAYED
B
13.7
K
R102
13.7
K
R100
2.67
K
R138
J1710
J53
J5+12VFE
+12VFE
FE
CONTROL OPTIONTO ENERGY
Varc FILTERED
ARC VOLT FILTER100V100p
C102
13.7
K
R106
13.7
K
R104
13.7
K
R107
13.7
K
R10513
.7K
R103
13.7
K
R101
B
8.95V
2901
CR 1( UNUSED
TO POWER BOARD
CONTACT )
L=PWM OFFH=PWM ON
100K
R23
5
C202
15.0
K
R212
100V330pC205
47.5
KR2
15 50V0.1C20410K
R214
D211
50V20C207
267
R229
1W3.3VDZ6
D210D209
10K
R24
0
D208D207
1.50K
R227
1.50K
R226
1.50K
R228
1.50K
R225
CR16
8
4
D206
1.30K
R222
ON=TRIGGER ONOFF=TRIGGER OFF
PWM_EN
PRI_FB
+15V
+15V
+15V+15V
3.6V
L=PWM ONH=PWM OFF
1.7V = 150A PRIMARY
C2901
2901A
( SHEET 1 )
10K
R213
10K
R23
7
X28 14
8
9
10.0
R20
3
10.0
R201
10.0
R20
2
10.0
R20
4
1N4936D202
1N4936D201
1.30
K
R24
2
10.0
R20
5
C201
26.7
R20
9
26.7
R207
267
R241
26.7
R208
+15V
1N4936D203
1N4936D204200V
.33
C200
100K
R23
2
10K
R23
6332K
R234
C206
10K
R23
3
AOP470
VARC_SCALED
13.7K
R115
50V0.1C10710K
CW
R140
BTURN10
.400V
243
R139
X3
SMP04
263
J51
1.820V
C108
10K
R137
8.25
K
R141
4 .75KR159
13.7K
R121
X41
2
3
47.5K
R110
4.75
K
R113
DV/DT VarcSAMPLE
DV/DT
DERI
VATI
VE_T
RIPA
Varc SAMPLENEW DV/DT
1V REF
1N914D101
J55
13.7K
R117
13.7K
R119
J56
FE
FE
NEG_CLAMP
FE
+12VFE
FE
+12VFE
+12VFE
FE
FE
+12VFE
+12VFE
+12VFE
FE
FE
3000V.0047
C100 47.5K
R112
1W12VDZ1
400V.001C101
4.75
K
R111
47.5K
R109
2781-BFV
2781-B5-19-95
2
7
5-24-96E
ELECTRICAL DIAGRAMS
INVERTEC STT & STT II
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PC Board Assembly - Control - Codes 10151 - 11092 - (G2782)
NOTE: Lincoln Electric assumes no responsibility for liablilities resulting from board level troubleshooting. PC Board repairs will invalidate your factory warranty. Individual Printed Circuit Board Components are not available from Lincoln Electric. This information is providedfor reference only. Lincoln Electric discourages board level troubleshooting and repair since it may compromise the quality of the design and may result in danger to the Machine Operator or Technician. Improper PC board repairs could result in damage to the machine.
G-8G-8
ITEM REQ'D PART NO IDENTIFICATIONIDENTIFICATIONPART NOREQ'DITEM
CAPACITORS = MFD/VOLTSRESISTORS = OHMS
J1 J4 J17J5 J27 J28 J2 J3
D10
5D
106
D200
D20
1D
202
D20
3D
204
D205
DZ1
DZ2
DZ3
DZ4
DZ5
DZ6
Q1
D10
1
D10
2
D103
D10
4
D107 D112
D113
D114
D20
6D
207
D20
8
D209
D21
0
D211
D100
D108
D109
D110
D111
C113
C114 C100
R15
1
R12
3
R127
R14
1R
146
R150
R111
R11
3
R12
8
R136
R159
R109
R110
R11
2
R11
4
R133
R211
R215
R231
R12
6
R23
4
R13
0
R13
1
R21
6
R210
R157
R22
9
R138
R14
9
R100 R101 R102 R103
R104 R105 R106 R107
R115
R116
R117
R118
R119
R120
R121
R122
R15
4R
155
R16
0R
161 R
225
R22
6
R22
7
R22
8
R212
R108 R162
R12
4
R21
7
R21
8
R21
9
R22
0
R22
1R
222
R22
3R
224
R13
7
R14
2
R14
5
R14
7
R148
R213
R214
R233
R237
R24
0
R14
3
R144 R232
R235
R134
R200
R201 R202 R203 R204 R205
R230
R20
6R
207
R208 R209
C122
C12
3
C12
4
C125
C12
6
C12
7
C12
8
C204 C211
R23
8
R239
C106
C205
C107
C121
C11
2C
116
C118
C120
C201
C202
C203
C206
C104
X6X5
X28
X2 X1
R14
0
C102
C10
3
C105
C11
9
C20
0
C11
1
CR
1
OCI7
OC
I1O
CI2
OC
I3
OC
I4
OC
I5
X3
C108
C20
7
C101
R43
3
C41
3
R47
0C
411
C43
0
R463
R461
R46
7
R46
6
C42
3 D41
2
R51
9
R51
3
DZ2
0D
Z9
C46
4
X35
R51
8
R52
1
R514
R52
2
R510
Q8
R525
R523
D410
R51
6R
517
R52
4
R50
9Q
7 D41
6R
512
R51
5
R48
9
C446
R47
8R
476
C447
D407
DZ15
C449
X29
D408 R475 R480
D406
R481
Q6
C469
R485
R47
7
R40
5
C409
DZ1
2
R50
7
R46
9
C404
DZ1
1
D40
9
C40
5
X31
X34
C466
C457
R403
R533
C402
DZ10
C403
C40
6
X22
R340
Q3
R33
3
X32
C42
9
R30
8R
309
D305
X17
C444
C45
6
X12 X2
0
X15X1
0
X13
X14
X9
X11
X18
X16
X19
X21
X23
X24
R30
1
R302
R313
R312 C304
C44
3
C435
R32
0
C306 R317
C433
C301 R303
R305
D30
0
R304
C30
2
C432
Q4
R322
C307
R323
R32
8
D301
C43
4
R314
C437
C445
C43
8
R33
2R
329
R325
R32
7
D30
4
R32
6
R31
6R
311
R310
R345
C309
DZ8
R34
2
Q9
R34
1
R31
9
R48
3R
484
X26
R482
R486 R487
R488
R51
1
D413
C462
DZ19
C463 R527
R528
R52
6
C41
2
C31
0
D306
D307
D308
C312
R33
7C31
4
X36
D411
R50
0
C460
DZ18
R50
1
C40
1
C40
0
X33
R50
5
R50
6R
400
R40
1
R40
4
D400
R43
4
R49
1
X30
R43
5
R44
3
R490 R
534
C452
D41
4
C45
4
R49
2
R49
3
R520
C451
DZ17
C455
D415
R496
C453
R440
C416
C450
R445
C417
R444
R448
R447
D404
R442
R499 C470
D418
D419
D417
R45
0
R52
9
R45
7
R458
R45
9
D40
5
C42
2
R455
R468 C414
R441
R449
D40
3
D402
R420
R419 R421
R422 R423
D401
C410
R532
R425
R427 R428
R426
R42
9
C42
4
C45
8
C42
8
C427
C426
C42
5
C46
8
C436
C46
7
C44
2
C441
C43
9
C44
0
C459
C419
R45
4R
456
D310
D309
DZ1
6
C465
C461
R30
0
C415
C407
R412
R41
3
R414
C44
8
R473
C308
R536
R479
STT
CO
NTR
OL
R158
R156
C11
7
R13
2R
129
R15
3
R13
5
R12
5
C110
C11
5
C300
C31
3
X8
R33
8R
339
R446
R47
1
R31
8C
305
D30
3
R321
C41
8
R439
R453
R41
7R
418
R472 R474 R432 R436 R437
R43
1
Q2
R343
X4
C10
9
R15
2
R50
4
R508
R40
7
R32
4
R494
R497 R498
R50
2
R503
R40
6
R411
R410 R409
R451
R452
R424
R49
5R344
R416
R415
D302
R306
R307
C303
C31
1
R334
R33
5
R408
R430
R242 R241
R236
R54
3
R54
2
R541
R561
R56
2R
563
D42
3
R560 D424
C475
R55
9
Q10
R55
0
R54
9
R548 R547
R54
6
R545 R544
R551
C472
R552
R55
5
C473
R564
R554
R55
3C
474
R539
C471
R53
7
R538
D420
R557
R33
0
D421
D422
R331
R16
4
D11
7D
116
R16
5D
115
R163
OC
I6
R139
R40
2
R54
0
R556
C12
9
R53
0
X25
W1
W2
W3
W4
G27
82-[
]
2782-1 5-19-95
7-28-95C
5-24-96E
STT INVERTER WELDER CONTROL P.C. BOARD ASSEMBLY
F.V.
FULL
2782-1 FV 6-8-94 L8441-3 t
UNLESS OTHERWISE SPECIFIED TOLERANCEON HOLE SIZES PER E2056ON 2 PLACE DECIMALS IS .02
WITH PUBLISHED STANDARDS.
ON 3 PLACE DECIMALS IS .002ON ALL ANGLES IS .5 OF A DEGREEMATERIAL TOLERANCE (" ") TO AGREE
THE LINCOLN ELECTRIC CO.CLEVELAND, OHIO U.S.A.
EQUIP.TYPE
SCALE
DR DATE CHK REF.
SUBJECT
SUP'S'D'GSHT.NO.
THE LINCOLN ELECTRIC CO.OWNED BY AND ISNOT TO BE REPRODUCED, DISCLOSED OR USED
THE LINCOLN ELECTRIC CO. G
GWITHOUT THE EXPRESS PERMISSION OF
THIS SHEET CONTAINS PROPRIETARY INFORMATION
G-9ELECTRICAL DIAGRAMS
INVERTEC STT & STT II
G-9R
etur
nto
Sec
tion
TOC
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urn
toS
ectio
nTO
CR
etur
nto
Sec
tion
TOC
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urn
toS
ectio
nTO
C
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toM
aste
rTO
CR
etur
nto
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ter
TOC
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urn
toM
aste
rTO
CR
etur
nto
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ter
TOC
Schematic - Control PC Board - Codes 11115 - 11116 - (G4649 Sheet 1 of 2)
NOTE: Lincoln Electric assumes no responsibility for liablilities resulting from board level troubleshooting. PC Board repairs will invalidate your factory warranty. Individual Printed Circuit Board Components are not available from Lincoln Electric. This information is providedfor reference only. Lincoln Electric discourages board level troubleshooting and repair since it may compromise the quality of the design and may result in danger to the Machine Operator or Technician. Improper PC board repairs could result in damage to the machine.
G-10ELECTRICAL DIAGRAMS
INVERTEC STT & STT II
G-10R
etur
nto
Sec
tion
TOC
Ret
urn
toS
ectio
nTO
CR
etur
nto
Sec
tion
TOC
Ret
urn
toS
ectio
nTO
C
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urn
toM
aste
rTO
CR
etur
nto
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ter
TOC
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toM
aste
rTO
CR
etur
nto
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ter
TOC
Schematic - Control PC Board - Codes 11115 - 11116 - (G4649 Sheet 2 of 2)
NOTE: Lincoln Electric assumes no responsibility for liablilities resulting from board level troubleshooting. PC Board repairs will invalidate your factory warranty. Individual Printed Circuit Board Components are not available from Lincoln Electric. This information is providedfor reference only. Lincoln Electric discourages board level troubleshooting and repair since it may compromise the quality of the design and may result in danger to the Machine Operator or Technician. Improper PC board repairs could result in damage to the machine.
ELECTRICAL DIAGRAMS
INVERTEC STT & STT II
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urn
toS
ectio
nTO
CR
etur
nto
Sec
tion
TOC
Ret
urn
toS
ectio
nTO
CR
etur
nto
Sec
tion
TOC
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urn
toM
aste
rTO
CR
etur
nto
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ter
TOC
Ret
urn
toM
aste
rTO
CR
etur
nto
Mas
ter
TOC
PC Board Assembly - Control - Codes 11115 - 11116 - (G4648)
NOTE: Lincoln Electric assumes no responsibility for liablilities resulting from board level troubleshooting. PC Board repairs will invalidate your factory warranty. Individual Printed Circuit Board Components are not available from Lincoln Electric. This information is providedfor reference only. Lincoln Electric discourages board level troubleshooting and repair since it may compromise the quality of the design and may result in danger to the Machine Operator or Technician. Improper PC board repairs could result in damage to the machine.
G-11G-11
G-12ELECTRICAL DIAGRAMS
INVERTEC STT & STT II
X414
13
12
P6 J64
267
R24
4.75
K
R23
P6 J65
D12
5.11
K
R25
D10D8
C11
P6 J610
LM350
ADJ
OUTIN X5
33.2K
R13J14
4
D11
50050V
C10
15.0K
R14
P6 J69
15J50VTP2
D9
C7
X41
2
3
Ch'ge.Sht.No.
COM
+24V
COMCOM
C
24Vac
A
ON 3 PLACE DECIMALS IS + .OO2ON 2 PLACE DECIMALS IS + .O2
ON HOLES SIZES PER E-2056
ON ALL ANGLES IS + .5 OF A DEGREEMATERIAL TOLERANCE ("t") TO AGREE
UNLESS OTHERWISE SPECIFIED TOLERANCE
85
41J7
1
3
J142
4
J65
6
1
10
LM224
X4
4
11
33.2
KR1
6
1N4936D14
1W15VDZ1 S
G
D Q5
P7J74
X47
6
5
2.21K
R21
UNLESS OTHERWISE SPECIFIED) LABELS
SUP'S'D'G.
TYPE
VOLTAGE NET
DZ- 6D-
SUPPLY
C-R-
UNLESS OTHERWISE SPECIFIED)
SUBJECT
EQUIP.
161/4W.022/50V
FRAME CONNECTION
11/10/92SHT.
INVERTEC
MM
(
P7J72
P6J62
NO.
10K
R19
LAST NO. USED
33.2K
R17
14
COMMON CONNECTION
CHK.
(UNLESS OTHERWISE SPECIFIED)
NONE
69
475K
R12
COM
COM
B
IRF513
D13
X48
9
10
100K
R22
CNY17-3
OCI1
2
1
6
5
4
1.820V
C6
267K
R20
26.7K R18
C14
3920V
C540V600mAQ40
1W6.2VDZ6
10K
R11
100K
R10
100
R43
10K
R41
100
R42
150K
R9
33.2K
R15
16018
F
E
P6
J6
8
1.0A30V
D161.0A30V
D15
P7J77
CONTROLTRIGGER
TO PULSE
TOPILOTLIGHT
(-)
TOCONTROLBOARD(COM)
DIAGRAM MAY NOT SHOW THE EXACT COMPONENTS OR CIRCUITRY OF CONTROLS
WITH PUBLISHED STANDARDSDATE
TRANSFORMER
16018MJHDR.
HAVING A COMMON CODE NUMBER.
ELECTRICAL SYMBOLS PER E1537
GENERAL INFORMATION
EARTH GROUND CONNECTION
WITHOUT AFFECTING THE INTERCHANGEABILITY OF A COMPLETE BOARD, THIS
RESISTORS = Ohms (CAPACITORS = MFD
NOTES :
1A, 400VDIODES =
POWER BD SCHEMATIC
POWER SUPPLY SOURCE POINT
UNUSED
SCALECLEVELAND, OHIO U.S.A.
THE LINCOLN ELECTRIC CO.
FILENAME: M16018_6JA
M
TOCONTROL
BOARD(+15V)
PWMSIGNAL
TRANSFORMERFROM AUXILIARY
18Vac
LM350
PWMSIGNAL
TOPILOTLIGHT
(+)
N.A. SINCE COMPONENTS OR CIRCUITRY ON A PRINTED CIRCUIT BOARD MAY CHANGE
RELAY COILS
FROM PROTECTION BD.
P6J67
+15V
J142
267
R7
P7J78
+ t.24
R69
Vin + Vc
OUT
GND
N.I. IN
INV IN
X67
267
R8
P7
J7
1
1W12V
DZ5
P6
J6
1
100K
R6
15J50VTP1
D1 D3
ADJ
OUTINX1
5W1.0
R1
330050V
C1
243
R3
+ t
.25R44
D4
P7
J7
3
P6
J6
6
P7 J76
2.67
KR
2
P6
J6
3
1.0A30V
D71W12VDZ4
15050V
C3
D2
100K
R5
P7 J75
C2
D5
1.50
K R4
50V0.1C9
J143
J141
50V0.1C8
1.0A30V
D6
Vin + Vc
OUT
GND
N.I. IN
INV IN
X68
COM
+24V
COM
+24V
+24V
COM
D
+24V
3-22-919-11-92B6-25-93A9-24-93D
4-13-95C3-29-96L9-27-96F
10-25-96
G-12R
etur
nto
Sec
tion
TOC
Ret
urn
toS
ectio
nTO
CR
etur
nto
Sec
tion
TOC
Ret
urn
toS
ectio
nTO
C
Ret
urn
toM
aste
rTO
CR
etur
nto
Mas
ter
TOC
Ret
urn
toM
aste
rTO
CR
etur
nto
Mas
ter
TOC
Schematic - Power PC Board - All Codes - (M16018)
NOTE: Lincoln Electric assumes no responsibility for liablilities resulting from board level troubleshooting. PC Board repairs will invalidate your factory warranty. Individual Printed Circuit Board Components are not available from Lincoln Electric. This information is providedfor reference only. Lincoln Electric discourages board level troubleshooting and repair since it may compromise the quality of the design and may result in danger to the Machine Operator or Technician. Improper PC board repairs could result in damage to the machine.
ELECTRICAL DIAGRAMS
INVERTEC STT & STT II
CAPACITORS = MFD/VOLTS
ITEM REQ'D PART NO. IDENTIFICATION
INDUCTANCE = HENRYS
DC
B
F
E
PO
WER
BO
AR
D
X1
X5
C1
C3
C10
X4
TP2
TP1
J6 J14 J7
OC
I1
Q5
Q40
R44 R1
L803
3-[]
X67 X68
R69
R2
R3
R4
D5
R21
R22
R16
R17
R18
R19
C5
C7
R9
R10
R42
R14
R13
R12
R11
R20
D13
R15
D10
D8
DZ1
D11
D9
C11
C14
DZ6
R43
R41
R24 R23
R25
D12
D14
C6
D1
D3
D2
D4
C2
C9
D15
D16
R6
DZ5
R7
R5
DZ4
R8
D7
D6
C8
Ret
urn
toS
ectio
nTO
CR
etur
nto
Sec
tion
TOC
Ret
urn
toS
ectio
nTO
CR
etur
nto
Sec
tion
TOC
Ret
urn
toM
aste
rTO
CR
etur
nto
Mas
ter
TOC
Ret
urn
toM
aste
rTO
CR
etur
nto
Mas
ter
TOC
PC Board Assembly - Power - All Codes - (L8033)
NOTE: Lincoln Electric assumes no responsibility for liablilities resulting from board level troubleshooting. PC Board repairs will invalidate your factory warranty. Individual Printed Circuit Board Components are not available from Lincoln Electric. This information is providedfor reference only. Lincoln Electric discourages board level troubleshooting and repair since it may compromise the quality of the design and may result in danger to the Machine Operator or Technician. Improper PC board repairs could result in damage to the machine.
G-13G-13
G-14ELECTRICAL DIAGRAMS
INVERTEC STT & STT II
ON 2 PLACE DECIMALS IS + .O2
WITH PUBLISHED STANDARDS
ON HOLES SIZES PER E-2056
SUPPLY
POWER
Ch'ge.Sht.No.
RESISTORS = Ohms (CAPACITORS = MFD
1A, 400VDIODES =
BASEDRIVE
2 AMP
Sym
met
ricG
ate
Driv
eLa
yout
UNLESS OTHERWISE SPECIFIED)UNLESS OTHERWISE SPECIFIED)
(UNLESS OTHERWISE SPECIFIED)
ELECTRICAL SYMBOLS PER E1537(
GENERAL INFORMATION
.022/50V1/4W
NEGATIVE BIAS
HOLD - OFF
forDARLINGTON
NUMBER.
DZ-17
COMMON CONNECTION
R-
SUPPLY
LAST NO. USED
CHK.
VOLTAGE NET
LABELSC-
D-
EARTH GROUND CONNECTION
POWER SUPPLY SOURCE POINT
MLD NO.SHT.
318
03/23/94
FRAME CONNECTION
DR. DATE
13
SUP'S'D'G.
SCALE NONE
EQUIP.TYPE
SUBJECTCLEVELAND, OHIO U.S.A.
THE LINCOLN ELECTRIC CO.
BLACK
PAIR
BLUE
MODULE
TWISTED
B
C
E
DARLINGTON
FILE: M17581_1AB
3.92
K
R4
+V
1.50K
R3
D5
J134
J131
OCI1
HP2201
7
3
2
OCI1
Vcc
GND
HP2201
5
8
GND
50V0.1C14
330050V
C15
8A400V
D1
8A400V
D2
.5 5W
R1
8A400V
D3
8A400V
D4
J136
330050V
C12J13
2
J135
C16J13
3
GND
+V
NOT SHOW THE EXACT COMPONENTS OR CIRCUITRY OF CONTROLS HAVING A COMMON CODE
ON 3 PLACE DECIMALS IS + .OO2
MATERIAL TOLERANCE ("t") TO AGREEON ALL ANGLES IS + .5 OF A DEGREE
UNLESS OTHERWISE SPECIFIED TOLERANCE
WITHOUT AFFECTING THE INTERCHANGEABILITY OF A COMPLETE BOARD, THIS DIAGRAM MAYN.A. SINCE COMPONENTS OR CIRCUITRY ON A PRINTED CIRCUIT BOARD MAY CHANGE
10VAC
R
6VAC
R
6
1 3
4
J13
NOTES :
+15V
1
3
J12
4
2
WINDINGTRANSFORMER
AUXILLARY
OFF = Dar l ington OFF
M17581
STT CONTROL BOARD
1K
ON = Dar l ington ON
1.50K
R2
+V
50V0.1C6
10W
2.7
R10
10.0R6
D131N5402
S
G
D
100V
Q2
330050V
C9
1W18V
DZ3
D71N5402
10.0R7
D111N5402
10W
2.7
R9
D101N5402 1.
00K
R15D12
1N5402
10W2.7
R13
D91N5402
10W2.7
R14
J124
1000V500pC17
1.00
KR1
7
1.00
KR1
8
J121
1W18VDZ1
1000V500pC8
200V.33C10
6A100V
Q113
2
D81N5402 J12
2
10W
2.7
R11
D61N5402
1W12VDZ2
10W
2.7
R12
1.00
KR1
6
5W20
R8
267
R5
50V0.1C5 NC
GND
S V
OUT
IN OUT
GND
V S
X23
4
7
5
1
6
8
2
4429GND
+V
GND
J123
M17581
INVERTER WELDERSSCHEMATIC, DARLINGTON DRIVE
BS
4A
5-19-953-29-96L
G-14R
etur
nto
Sec
tion
TOC
Ret
urn
toS
ectio
nTO
CR
etur
nto
Sec
tion
TOC
Ret
urn
toS
ectio
nTO
C
Ret
urn
toM
aste
rTO
CR
etur
nto
Mas
ter
TOC
Ret
urn
toM
aste
rTO
CR
etur
nto
Mas
ter
TOC
Schematic - Darlington Drive Board - Codes 10151 - 10383 - (M17581)
NOTE: Lincoln Electric assumes no responsibility for liablilities resulting from board level troubleshooting. PC Board repairs will invalidate your factory warranty. Individual Printed Circuit Board Components are not available from Lincoln Electric. This information is providedfor reference only. Lincoln Electric discourages board level troubleshooting and repair since it may compromise the quality of the design and may result in danger to the Machine Operator or Technician. Improper PC board repairs could result in damage to the machine.
ELECTRICAL DIAGRAMS
INVERTEC STT & STT II
J12 J13
R15 R18 R17 R16
R14
R13
R10
R12
R9
R11
DZ1
C17
Q1
R6
D4
D1
D3
D2
R1
C12 C15
C16
OCI1
D5
R3
R2
D10
D11
D12
D13
R8
D6 D7 D8
D9
C10
C9
Q2 C
8DZ3
R7
C14
X2
C5D
Z2
R5
R4
C6
STT DARLINGTON DRIVE
ITEM REQ'D PART NO. IDENTIFICATION
CAPACITORS = MFD/VOLTS
XXX
XXX
XXX
XXX
XXX
XXX
XXX
XXX
XXX
XXX
XXX
XXX
XXX
XXX
XX XX
XX
XXX
XXXX
X X X
XX
X
XXXX
X X
X
X
X
XXX
XXX
RESISTORS = OHMS
G2778-[ ]
Ret
urn
toS
ectio
nTO
CR
etur
nto
Sec
tion
TOC
Ret
urn
toS
ectio
nTO
CR
etur
nto
Sec
tion
TOC
Ret
urn
toM
aste
rTO
CR
etur
nto
Mas
ter
TOC
Ret
urn
toM
aste
rTO
CR
etur
nto
Mas
ter
TOC
PC Board Assembly - Darlington Drive - Codes 10151 - 10383 - (G2778)
NOTE: Lincoln Electric assumes no responsibility for liablilities resulting from board level troubleshooting. PC Board repairs will invalidate your factory warranty. Individual Printed Circuit Board Components are not available from Lincoln Electric. This information is providedfor reference only. Lincoln Electric discourages board level troubleshooting and repair since it may compromise the quality of the design and may result in danger to the Machine Operator or Technician. Improper PC board repairs could result in damage to the machine.
G-15G-15
G-16ELECTRICAL DIAGRAMS
INVERTEC STT & STT II
G-16R
etur
nto
Sec
tion
TOC
Ret
urn
toS
ectio
nTO
CR
etur
nto
Sec
tion
TOC
Ret
urn
toS
ectio
nTO
C
Ret
urn
toM
aste
rTO
CR
etur
nto
Mas
ter
TOC
Ret
urn
toM
aste
rTO
CR
etur
nto
Mas
ter
TOC
Schematic - IGBT Drive Board - Codes 11090 - 11116 - (L12144)
NOTE: Lincoln Electric assumes no responsibility for liablilities resulting from board level troubleshooting. PC Board repairs will invalidate your factory warranty. Individual Printed Circuit Board Components are not available from Lincoln Electric. This information is providedfor reference only. Lincoln Electric discourages board level troubleshooting and repair since it may compromise the quality of the design and may result in danger to the Machine Operator or Technician. Improper PC board repairs could result in damage to the machine.
ELECTRICAL DIAGRAMS
INVERTEC STT & STT II
Ret
urn
toS
ectio
nTO
CR
etur
nto
Sec
tion
TOC
Ret
urn
toS
ectio
nTO
CR
etur
nto
Sec
tion
TOC
Ret
urn
toM
aste
rTO
CR
etur
nto
Mas
ter
TOC
Ret
urn
toM
aste
rTO
CR
etur
nto
Mas
ter
TOC
PC Board Assembly - IGBT Drive - Codes 11090 - 11116 - (L12145)
NOTE: Lincoln Electric assumes no responsibility for liablilities resulting from board level troubleshooting. PC Board repairs will invalidate your factory warranty. Individual Printed Circuit Board Components are not available from Lincoln Electric. This information is providedfor reference only. Lincoln Electric discourages board level troubleshooting and repair since it may compromise the quality of the design and may result in danger to the Machine Operator or Technician. Improper PC board repairs could result in damage to the machine.
G-17G-17
G-18ELECTRICAL DIAGRAMS
INVERTEC STT & STT II
W
W
R
600mA40V
Q7
1W3.3VDZ5
1.00K
R12
1/2W1
R15
100V1A
Q2
600mA40V
Q6
15.0K
R10
50V2700pC2
47.5
R35
1N4936D9
600mA40V
Q5
1W10VDZ1
1N4936D3
1W6.2V
DZ6
100V1A
Q3
1W10VDZ3
1/2W1
R11
1 .50KR7
1N4936D5
22.1K
R16
1N4936D2
40V600mAQ4
221
R4
100
R5
1.00K
R14
C1
20
R13
100R3
2N4401
2N4403
IRFD110
IRFD110
2N4403
2N4403
475
R42
RESISTORSNUBBER
1
---401
8
403
-
WIT
HPU
BLI
SHED
STAN
DAR
DS
8440
TRANSFORMER
LU
NLE
SSO
THER
WIS
ESP
ECIF
I ED
TOLE
RAN
CE
NO
TES
:
NU
MBE
R .
ON
HO
LES
SIZE
SPE
RE-
2056
ON
2PL
ACE
DEC
I MAL
SIS
+.O
2
R
Ch'g
e.Sht
.No.
CAPACITOR
ON
ALL
ANG
LES
IS+
.5O
FA
DEG
REE
MAT
ERI A
LTO
LERA
NC
E("t
")TO
AGR E
E
ON
3PL
ACE
DEC
IMAL
SIS
+.O
O2
FRANCE CANADA AUSTRALIA
INPUT12 NEGATIVE
PRIMARY
39.2K
R38
1N4936D10
600mA40V
Q8
100
R24
40V600mAQ12
22.1K
R23
475
R291N4936
D8
C5
39.2K
R41
1200V.047C4
39.2K
R40
BYT30P600
A2
C2A1
2N4401
2N4403
IRFD110
IRFD110
2N4403
2N4403
A
1/2W1
R28
475R
37
C6
10.0
R27
10.0
R34
10.0
R26
10.0
R25
G1
IRFP460
D2
S4
D1 D3
G2
D4
S2 S5
D5
G3
S1G5
G4
S3
A110.0
R19
1W15VDZ7
100V1A
Q1
1/2W1
R22
1W10VDZ12
50V2700pC8
100V1A
Q10
15.0K
R32
1W10VDZ2 600mA
40V
Q9
1N4936D7
1W6.2V
DZ9
47.5
R36
BYT12P600C1
A1
A1
39.2K
R39
221
R2
1.00K
R21
20
R31
1 .50KR30
100R1
1N4936D6
600mA40V
Q11
1W3.3VDZ8
1N4936D1
1.00K
R20
CAP
ACIT
OR
S=
B
NO.
GEN
ERAL
INFO
RM
ATIO
N
(1 /
4 W.0
2 2/5
0VLA
BEL
S(U
NLE
S SO
T HE R
WIS
ESP
E CI F
IED
)
UN
LESS
OT H
ERW
I SE
S PE C
IFI E
D)
R ESI
STO
RS=
Ohm
s(
1 A,4
0 0V
8440
NO
NE
M.A.
P.
THE
LIN
CO
LNEL
ECTR
ICC
O.
CHK.
C-
D-
8
SC
ALE
DA
TE
S UP P
LYV O
LTAG
EN
E T
FRAM
EC
ON
NE C
TIO
N
CO
MM
ON
CO
NN
E CT I
ON
INVE
RTE
CV3
00EQ
UIP.
LSH
T.
42 10
SUP'
S'D'
G.
CLEV
ELAN
D,O
HIO
U.S.
A.TY
PE
SU
BJE
CT
MFD
---
4
402404
POSITIVE
1N4936D4
1W15VDZ4
475
R18
10.0
R9
10.0
R8
10.0
R17
10.0
R33
C7
10.0
R6
RESISTORSNUBBER
POW
ERSU
PPLY
SOU
RC
EPO
INT
EAR
THG
RO
UN
DC
ON
NE C
TIO
N
DR.
DI O
DE S
=
LAS T
NO
.US E
D
R-
SW
ITC
HB
OA
RD
SC
HEM
ATI
C
NO
TS H
OW
THE
E XAC
TC
OM
PON
E NTS
OR
CI R
CU
ITR
YO
FC
ON
T RO
LSH
AVIN
GA
CO
MM
ON
CO
DE
WIT
HO
UT
AFFE
CTI
NG
T HE
INTE
RC
HA N
GEA
BIL
ITY
OF
AC
OM
PLE T
EB
OA R
D,T
HIS
DIA
GR
A MM
AYN
.A.
SIN
CE
CO
MPO
NEN
T SO
RC
IRC
UIT
RYO
NA
P RIN
T ED
CIR
CU
ITB O
ARD
MAY
CH
ANG
E
UN
LES S
OT H
E RW
ISE
SPE C
I FIE
D)
E LE C
T RIC
A LS Y
MB
OLS
PER
E 15 3
7
PRIMARY5-
FILTERINPUT
TRANSFORMER
9 INPUT
1200V.047C3
BYT30P600
A2
C2
A2
G1
IRFP460
D2
S4
D1 D3
G2
D4
S2 S5
D5
G3
S1G5
G4
S3
A2BYT12P600
C1
A1
A2
FILE
NO
.L84
40-1
AA
11-2
5-91
BS
9-11
-92
10-8
-93A
G-18R
etur
nto
Sec
tion
TOC
Ret
urn
toS
ectio
nTO
CR
etur
nto
Sec
tion
TOC
Ret
urn
toS
ectio
nTO
C
Ret
urn
toM
aste
rTO
CR
etur
nto
Mas
ter
TOC
Ret
urn
toM
aste
rTO
CR
etur
nto
Mas
ter
TOC
Schematic - Switch Board - All Codes - (L8440)
NOTE: Lincoln Electric assumes no responsibility for liablilities resulting from board level troubleshooting. PC Board repairs will invalidate your factory warranty. Individual Printed Circuit Board Components are not available from Lincoln Electric. This information is providedfor reference only. Lincoln Electric discourages board level troubleshooting and repair since it may compromise the quality of the design and may result in danger to the Machine Operator or Technician. Improper PC board repairs could result in damage to the machine.
ELECTRICAL DIAGRAMS
INVERTEC STT & STT II
Ret
urn
toS
ectio
nTO
CR
etur
nto
Sec
tion
TOC
Ret
urn
toS
ectio
nTO
CR
etur
nto
Sec
tion
TOC
Ret
urn
toM
aste
rTO
CR
etur
nto
Mas
ter
TOC
Ret
urn
toM
aste
rTO
CR
etur
nto
Mas
ter
TOC
PC Board Assembly - Switch - All Codes - (L8441)
NOTE: Lincoln Electric assumes no responsibility for liablilities resulting from board level troubleshooting. PC Board repairs will invalidate your factory warranty. Individual Printed Circuit Board Components are not available from Lincoln Electric. This information is providedfor reference only. Lincoln Electric discourages board level troubleshooting and repair since it may compromise the quality of the design and may result in danger to the Machine Operator or Technician. Improper PC board repairs could result in damage to the machine.
G-19G-19
ITEM REQ'D PART NO. IDENTIFICATION
2
2
S16668-5 .022/50C1, C5, C6, C7
C3, C4C2, C8
4
2 S13490-112 .047/12002 S16668-4 2700pF/50
D1, D2, D3, D4, D5, D6,D7, D8, D9, D10 10 T12705-34 1N4936
2DZ1, DZ2, DZ3, DZ12DZ4, DZ7
T12702-27 1N47404T12702-29 1N4744AT12702-40 1N4735
Q4, Q12 2 T12704-686 T12704-69 2N4403
2N4401Q1, Q2, Q3, Q10 4 T12704-73 IC PKG MOSFET
R1, R3, R5, R24 4 S19400-1000 100 1/4WR2, R4 2 S19400-2210 221 1/4W
10 S19400-10R0 10 1/4W
R7, R30 2 S19400-1501 1.5K 1/4WR10, R32 S19400-1502 15K 1/4WR11, R15, R22, R28 4 T14231-20 1 1/2W
4R12, R14, R20, R21 S19400-1001 1K 1/4W
22
2
R13, R31R16, R23
R38, R39, R40, R41
R18, R29, R37, R42R35, R36
4
4
R6, R8, R9, R17, R19, R25R26, R27, R33, R34
S19400-20R0 20 1/4WS19400-2212 22.1K 1/4WS19400-4750 475 1/4WS19400-47R5 47.5 1/4WS19400-3922 39.2K 1/4W
Q5, Q6, Q7, Q8, Q9, Q11
DZ6, DZ9DZ5, DZ8 2 T12702-53 3.3V 1W
C3 C4
SWITCH
R19
R26
R25
R27
R34
R33 R9
R6
R8
R17
R29
R1
R3
R18
R21
R23
R20
R30
R31
R24
R2
R32
R4
R5
R7
R10
R12
R13
R14
R16
R41
R40
R39
R38
R42
R37
R36
R35
C2
C8
C7
C1
C6
C5
C3 C4
DZ2DZ1 D9
D10
D5
D4
D3
D2
DZ6
DZ4
DZ3
D8
DZ7
DZ1
2D
7D
Z9
D1
D6
Q10 Q1Q3 Q2
B10 B3 B12 B1 B5 B9 B6 B7 B2 B11
R15 R
11
R28 R22
B4 B8
Q7
Q6
Q5
Q4
Q9
Q8
Q12
Q11
L8441-[ ]
DZ5
DZ8
G-20ELECTRICAL DIAGRAMS
INVERTEC STT & STT II
G-20R
etur
nto
Sec
tion
TOC
Ret
urn
toS
ectio
nTO
CR
etur
nto
Sec
tion
TOC
Ret
urn
toS
ectio
nTO
C
Ret
urn
toM
aste
rTO
CR
etur
nto
Mas
ter
TOC
Ret
urn
toM
aste
rTO
CR
etur
nto
Mas
ter
TOC
Schematic - Driver Board - All Codes - (S20799)
NOTE: Lincoln Electric assumes no responsibility for liablilities resulting from board level troubleshooting. PC Board repairs will invalidate your factory warranty. Individual Printed Circuit Board Components are not available from Lincoln Electric. This information is providedfor reference only. Lincoln Electric discourages board level troubleshooting and repair since it may compromise the quality of the design and may result in danger to the Machine Operator or Technician. Improper PC board repairs could result in damage to the machine.
Capacitor Pre-charging Circuits
J16
7
J113
J16
8
100
R12
DRIVE
GATE
GATE
GATE
GATE
T1
6
3
7
104
9
8
5
1
12
J91
J94
J93
J111
J104
150K
R6
100
R74A900V
Q1
20W
250
R1
1W12V
DZ1
150K
R3
150K
R4
20W250R2
150K
R5
J96
J106
J16
3
J101
J103
20W250R14
J16
1
1W12V
DZ2
150K
R10
150K
R11
4A900V
Q2
150K
R9
20W250
R13
150K
R8
J16
2
J16
13
J16
12
20799
Power Switch Drive Transformer
11-4-92LC
Ch'ge.Sht.No.
J11
S4 PROTECTION
N.A. SINCE COMPONENTS OR CIRCUITRY ON A PRINTED CIRCUIT BOARD MAY CHANGEWITHOUT AFFECTING THE INTERCHANGEABILITY OF A COMPLETE BOARD, THIS DIAGRAM MAY
DATE
SUBJECT
EQUIP.TYPE
S2
NOTES :
NOT SHOW THE EXACT COMPONENTS OR CIRCUITRY OF CONTROLS HAVING A COMMON CODENUMBER.
G1
FROM
SUP'S'D'G.
ON 3 PLACE DECIMALS IS + .OO2
S3
WITH PUBLISHED STANDARDS
UNLESS OTHERWISE SPECIFIED TOLERANCE
CLEVELAND, OHIO U.S.A.
TO POWER
BOARD
TO
ON HOLES SIZES PER E-2056
SWITCH
64
1 3
J16
MATERIAL TOLERANCE ("t") TO AGREES
G2
DR.
SCALE
THE LINCOLN ELECTRIC CO.
G4
BOARD
S1
G3
NONE
CHK.
PROTECTION
SHT.NO. S
J9,J10
4
1 2
3
ON ALL ANGLES IS + .5 OF A DEGREE
ON 2 PLACE DECIMALS IS + .O2
BD.
20799
FROM
BD.
J16
14
7
14
1
8
FILE: S20799-1AA
INVERTER WELDERS
SCHEMATIC, DRIVER BOARD
BS
6-25-93C
ELECTRICAL DIAGRAMS
INVERTEC STT & STT II
Ret
urn
toS
ectio
nTO
CR
etur
nto
Sec
tion
TOC
Ret
urn
toS
ectio
nTO
CR
etur
nto
Sec
tion
TOC
Ret
urn
toM
aste
rTO
CR
etur
nto
Mas
ter
TOC
Ret
urn
toM
aste
rTO
CR
etur
nto
Mas
ter
TOC
PC Board Assembly - Driver - All Codes - (L9134)
NOTE: Lincoln Electric assumes no responsibility for liablilities resulting from board level troubleshooting. PC Board repairs will invalidate your factory warranty. Individual Printed Circuit Board Components are not available from Lincoln Electric. This information is providedfor reference only. Lincoln Electric discourages board level troubleshooting and repair since it may compromise the quality of the design and may result in danger to the Machine Operator or Technician. Improper PC board repairs could result in damage to the machine.
G-21G-21
CAPACITORS = MFD/VOLTS
ITEM REQ'D PART NO. IDENTIFICATION
INDUCTANCE = HENRYS
T1
J9 J10
J11
J16
R7
DZ1Q1
R1 R2
R3
R4
R5
R6
Q2
R13 R14
DZ2 R12
R11
R10
R9
R8
L9134-[ ]DRIVER
XXXXXXX
XXXXXXX
XXXX
XXXX
XXXXX
XXXXXXXXXXXXX
XXXX XXXXXXXXXXXX
XXXX XXXXRESISTORS = OHMS/WATTS
G-22ELECTRICAL DIAGRAMS
INVERTEC STT & STT II
G-22R
etur
nto
Sec
tion
TOC
Ret
urn
toS
ectio
nTO
CR
etur
nto
Sec
tion
TOC
Ret
urn
toS
ectio
nTO
C
Ret
urn
toM
aste
rTO
CR
etur
nto
Mas
ter
TOC
Ret
urn
toM
aste
rTO
CR
etur
nto
Mas
ter
TOC
Schematic - Protection PC Board - Codes 10151 - 11092 - (M16097)
NOTE: Lincoln Electric assumes no responsibility for liablilities resulting from board level troubleshooting. PC Board repairs will invalidate your factory warranty. Individual Printed Circuit Board Components are not available from Lincoln Electric. This information is providedfor reference only. Lincoln Electric discourages board level troubleshooting and repair since it may compromise the quality of the design and may result in danger to the Machine Operator or Technician. Improper PC board repairs could result in damage to the machine.
2735V
C2
1.82K
R3
J15
6
J15
3
332
R35
267K
R36
50V.022C4
1W10VDZ1
CNY17-3VOCI4
42
1
6
5
10K
R26
332K
R22
X11
2
3
D6
56.2K
R9
1.82K
R16
1 .82K
R13
150K
R11
10K
R28
D4 15.0K
R33
CW
5KR7
150K
R12
267K
R34
CW
5KR20
332
R37
J15
1
50V.022C3
GND
IN OUTX2
J15
4
CNY17-3VOCI3
42
1
6
5
+5V
+5V
TO CONTROL BD.
(Single Phase)C5
CNY17-3VOCI1
42
1
6
5
J84
CHK.
15.0K
R25
SUBJECT
15.0K
R24
NO.DATEDR.
CLEVELAND, OHIO U.S.A.SHT.
EARTH GROUND CONNECTION
MMSUP'S'D'G.
NONE
TYPE
_
R-
LAST NO. USED
INVERTEC V300
PROTECTIONSCALE
POWER SUPPLY SOURCE POINT
_
_
(Over Voltage)
C-
TO DRIVER BD.
D-
VOLTAGE NET
COMMON CONNECTION
FRAME CONNECTION
WITH PUBLISHED STANDARDS
1/4W(
UNLESS OTHERWISE SPECIFIED).022/50V
EQUIP.
(UNLESS OTHERWISE SPECIFIED)1A, 400V
UNLESS OTHERWISE SPECIFIED)
SUPPLY
WITHOUT AFFECTING THE INTERCHANGEABILITY OF A COMPLETE BOARD, THIS DIAGRAM MAYNOT SHOW THE EXACT COMPONENTS OR CIRCUITRY OF CONTROLS HAVING A COMMON CODE
LABELS
ELECTRICAL SYMBOLS PER E1537
N.A. SINCE COMPONENTS OR CIRCUITRY ON A PRINTED CIRCUIT BOARD MAY CHANGE
RESISTORS = Ohms (CAPACITORS = MFD
DIODES =
GENERAL INFORMATION
MATERIAL TOLERANCE ("t") TO AGREEON ALL ANGLES IS + .5 OF A DEGREE
ON 3 PLACE DECIMALS IS + .OO2
(Over Voltage)
UNLESS OTHERWISE SPECIFIED TOLERANCE Ch'ge.Sht.No.ON HOLES SIZES PER E-2056
ON 2 PLACE DECIMALS IS + .O2
TO DRIVER BD.
M
FROM (-) LOWER CAPACITOR
FROM (+) UPPER CAPACITOR
FROM BLEEDER RESISTOR
16097
15.0KR30
X114
13
12
FROM (-) UPPER CAPACITOR
THE LINCOLN ELECTRIC CO.
J82
15.0K
R31
15.0K
R23
1N4007D8
LM224
X1
4
11
15.0K
R29
C1
D3
+5V
H5
NUMBER.
NOTES :
FROM CENTER LEG OF INPUT
B51
B14
B53
D7
681K
R1
+5V
56.2K
R10
+5V
150K
R5
C6
X17
6
5
D5
10K
R32
CNY17-3VOCI2
42
1
6
5
(Over Voltage)TO POWER BD.D1
X18
9
10
56.2K
R6
B52J8
1
100K
R14
3.32K
R19
475
R15
56.2K
R27
10K
R18
J83
56.2K
R8
150K
R4
15.0K
R21
681K
R2
FILE: M
16097BS/DB 9-7-89 TJP
1-25-919-11-92B
16097-2F1
12-10-93A
ELECTRICAL DIAGRAMS
INVERTEC STT & STT II
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urn
toS
ectio
nTO
CR
etur
nto
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tion
TOC
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urn
toS
ectio
nTO
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etur
nto
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tion
TOC
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aste
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etur
nto
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ter
TOC
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urn
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aste
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CR
etur
nto
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ter
TOC
PC Board Assembly - Protection - Codes 10151 - 11092 - (L7915)
NOTE: Lincoln Electric assumes no responsibility for liablilities resulting from board level troubleshooting. PC Board repairs will invalidate your factory warranty. Individual Printed Circuit Board Components are not available from Lincoln Electric. This information is providedfor reference only. Lincoln Electric discourages board level troubleshooting and repair since it may compromise the quality of the design and may result in danger to the Machine Operator or Technician. Improper PC board repairs could result in damage to the machine.
G-23G-23
PR
OTEC
TION
52
5314
H5
51
L7915-[]
R37
R34 R36
R35
R12
R14
R13
R23
R24
R25
R29
R31
R30
R16
R33
R19 R28
R21
R22
R15
R1 R2
R3
R4
R9
R10
R8
R27
R6
R5
R11
R32
R26
R18
C1
C3 C4
C2
DZ1
D8
D7
D1
D5
D4
D6
D3
X1
J8
J15
OCI1 OCI2
OCI4 OCI3
B5
B53
B52
B51
B14
R20
R7
X2
C5 C6
G-24ELECTRICAL DIAGRAMS
INVERTEC STT & STT II
G-24R
etur
nto
Sec
tion
TOC
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urn
toS
ectio
nTO
CR
etur
nto
Sec
tion
TOC
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urn
toS
ectio
nTO
C
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toM
aste
rTO
CR
etur
nto
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ter
TOC
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urn
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aste
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etur
nto
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ter
TOC
Schematic - Protection PC Board - Codes 11115 - 11116 - (M20352)
NOTE: Lincoln Electric assumes no responsibility for liablilities resulting from board level troubleshooting. PC Board repairs will invalidate your factory warranty. Individual Printed Circuit Board Components are not available from Lincoln Electric. This information is providedfor reference only. Lincoln Electric discourages board level troubleshooting and repair since it may compromise the quality of the design and may result in danger to the Machine Operator or Technician. Improper PC board repairs could result in damage to the machine.
ELECTRICAL DIAGRAMS
INVERTEC STT & STT II
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urn
toS
ectio
nTO
CR
etur
nto
Sec
tion
TOC
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urn
toS
ectio
nTO
CR
etur
nto
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tion
TOC
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urn
toM
aste
rTO
CR
etur
nto
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ter
TOC
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urn
toM
aste
rTO
CR
etur
nto
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ter
TOC
PC Board Assembly - Protection - Codes 11115 - 11116 - (L12235)
NOTE: Lincoln Electric assumes no responsibility for liablilities resulting from board level troubleshooting. PC Board repairs will invalidate your factory warranty. Individual Printed Circuit Board Components are not available from Lincoln Electric. This information is providedfor reference only. Lincoln Electric discourages board level troubleshooting and repair since it may compromise the quality of the design and may result in danger to the Machine Operator or Technician. Improper PC board repairs could result in damage to the machine.
G-25G-25
G-26ELECTRICAL DIAGRAMS
INVERTEC STT & STT II
G-26R
etur
nto
Sec
tion
TOC
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urn
toS
ectio
nTO
CR
etur
nto
Sec
tion
TOC
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urn
toS
ectio
nTO
C
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urn
toM
aste
rTO
CR
etur
nto
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ter
TOC
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urn
toM
aste
rTO
CR
etur
nto
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ter
TOC
Schematic - Current Sense PC Board - All Codes - (S21410)
NOTE: Lincoln Electric assumes no responsibility for liablilities resulting from board level troubleshooting. PC Board repairs will invalidate your factory warranty. Individual Printed Circuit Board Components are not available from Lincoln Electric. This information is providedfor reference only. Lincoln Electric discourages board level troubleshooting and repair since it may compromise the quality of the design and may result in danger to the Machine Operator or Technician. Improper PC board repairs could result in damage to the machine.
C1
20K
CW
R6
2KCW
R2
6.81KR7
1.50
KR1
1.00K
R4
50V150pC2
X1 1
2
3
1.00
KR
3
100
R5
681K
R11
10.0
K
R16
13.7K
R9
681KR8
J181
X17
6
5
13.7K
R10
X1 8
9
10
+VH
-VH
-IC
+IC
X2 1
4
2
3
1.50KR14
X3
TL431 REF8
1
6
100
R12
50V0.1C4
LT1014
X1
4
11
50V50C3
J182
C5X1 14
13
12
2.94K
R13
10.0
R15
J183
+15V
+15V
100V3AQ1
J184
CURRENT CAL
FILE: S21410_1BA
SENSOR
3.8V = 38 mA
EXCITATION CURRENT MIN OFF SETADJUSTMENT
HALL EFFECT
100A/V CURRENT OUT
1014
S
1014
1.6V = 16 mA
VREF
SOURCE
21410
1014
THE LINCOLN ELECTRIC CO.
NOTES :
UNLESS OTHERWISE SPECIFIED)BOARD.
1J18
2
43
EARTH GROUND CONNECTION
THE LINCOLN ELECTRIC CO.AND IS NOT TO BE REPRODUCED, DISCLOSED OR USED WITHOUT THE EXPRESS PERMISSION OF
VOLTAGE NET
POWER SUPPLY SOURCE POINT
LABELS
FRAME CONNECTIONSUPPLY
1014
ELECTRICAL SYMBOLS PER E1537
21410
UNLESS OTHERWISE SPECIFIED TOLERANCE
RESISTORS = Ohms (
SINCE COMPONENTS OR CIRCUITRY ON
CODE NUMBER.
ON HOLES SIZES PER E-2056
THE INTERCHANGEABILITY
Ch'ge.Sht.No.
SHOW THE EXACT COMPONENTS
OR CIRCUITRY OF
THIS SHEET CONTAINS PROPRIETARY INFORMATION OWNED BY
( UNLESS OTHERWISE SPECIFIED)
N.A.
OF A COMPLETE
A PRINTED
THIS DIAGRAM MAY NOT
CIRCUIT BOARD
1A, 400VDIODES =
ON 3 PLACE DECIMALS IS + .OO2
MAY CHANGE
1/4W
GENERAL INFORMATION
CAPACITORS = .022/50VWITHOUT AFFECTING
MFD
EQUIP.
NONEON 2 PLACE DECIMALS IS + .O2
CONTROLS HAVING A COMMON
ON ALL ANGLES IS + .5 OF A DEGREE
(UNLESS OTHERWISE SPECIFIED)
MATERIAL TOLERANCE ("t") TO AGREE
COMMON CONNECTION
SCHEMATIC
DR. SUP'S'D'G.DATE SCHK.SHT.NO.MLD
WITH PUBLISHED STANDARDS
SCALE03/21/94
STT-CURRENT SENSE
SUBJECTCLEVELAND, OHIO U.S.A.TYPETHE LINCOLN ELECTRIC CO.
FV
5-19-95
9-27-96F
11-15-96E
ELECTRICAL DIAGRAMS
INVERTEC STT & STT II
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urn
toS
ectio
nTO
CR
etur
nto
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tion
TOC
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urn
toS
ectio
nTO
CR
etur
nto
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tion
TOC
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urn
toM
aste
rTO
CR
etur
nto
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ter
TOC
Ret
urn
toM
aste
rTO
CR
etur
nto
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ter
TOC
PC Board Assembly - Current Sense - All Codes - (M17591)
NOTE: Lincoln Electric assumes no responsibility for liablilities resulting from board level troubleshooting. PC Board repairs will invalidate your factory warranty. Individual Printed Circuit Board Components are not available from Lincoln Electric. This information is providedfor reference only. Lincoln Electric discourages board level troubleshooting and repair since it may compromise the quality of the design and may result in danger to the Machine Operator or Technician. Improper PC board repairs could result in damage to the machine.
G-27G-27
C1
C2 C5
J18
R1 R2
R3
R4
R5
R6 R7
R8 R9
R10 R11
R12
X1
STT CURRENT SENSE
R13
R14 R15
R16
X3 C4
C3
M17
591-
[]
X2
ITEM REQ'D PART NO. DESCRIPTION
CAPACITORS = MFD/VOLTS
XXXX
XXXX
XX
XXXXXX XXX
XXXXXXXXXX
XX XXX XXX
XXXX
X
XXXX
X X X
X X
Q1
G-28ELECTRICAL DIAGRAMS
INVERTEC STT & STT II
G-28R
etur
nto
Sec
tion
TOC
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urn
toS
ectio
nTO
CR
etur
nto
Sec
tion
TOC
Ret
urn
toS
ectio
nTO
C
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urn
toM
aste
rTO
CR
etur
nto
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ter
TOC
Ret
urn
toM
aste
rTO
CR
etur
nto
Mas
ter
TOC
Schematic - Remote Protection PC Board - All Codes - (M17609)
NOTE: Lincoln Electric assumes no responsibility for liablilities resulting from board level troubleshooting. PC Board repairs will invalidate your factory warranty. Individual Printed Circuit Board Components are not available from Lincoln Electric. This information is providedfor reference only. Lincoln Electric discourages board level troubleshooting and repair since it may compromise the quality of the design and may result in danger to the Machine Operator or Technician. Improper PC board repairs could result in damage to the machine.
J361
600V.05C15
3000V.0047C7
.39mH
L6.39mH
L5
.39mH
L3
3KV.0047C63KV
.0047C1
3KV.0047C43KV
.0047C3
3KV.0047C2 3KV
.0047C5
J3616
J365
.39mH
L2
J333
J356
J3612
J3614
J3613
J368
J332
J3610
J3611
J336
J345
J346
3000V.0047C8
J362
J337
3000V.0047C9
160J320V
TP1
B25W1200
R1
J364
J353
J354
J367
80J150VTP3
J351
3000V.0047C11
3000V.0047C10
J355
J352
J344
J348
J335
B1
160J320V
TP2
J3615
3000V.0047C12
600V.05C16
J334
J366
.39mH
L4
.39mH
L7
J338
J369
J341
(+) STUD
(-) STUD5W1200
R2
TYPE
SUBJECTNONE
CHASSISCHASSIS CHASSIS
04/20/94
3000V.0047C14 J37
3
332
R4J37
1
3000V.0047
C13
J3310
332
R8
332
R3
332
R5
332
R6J33
9
DATE
UNLESS OTHERWISE SPECIFIED)
NOTES :
NUMBER.NOT SHOW THE EXACT COMPONENTS OR CIRCUITRY OF CONTROLS HAVING A COMMON CODE
N.A. SINCE COMPONENTS OR CIRCUITRY ON A PRINTED CIRCUIT BOARD MAY CHANGEWITHOUT AFFECTING THE INTERCHANGEABILITY OF A COMPLETE BOARD, THIS DIAGRAM MAY
GENERAL INFORMATION
ON ALL ANGLES IS + .5 OF A DEGREEON 3 PLACE DECIMALS IS + .OO2
ON HOLES SIZES PER E-2056
ELECTRICAL SYMBOLS PER E1537
MATERIAL TOLERANCE ("t") TO AGREE
UNLESS OTHERWISE SPECIFIED TOLERANCE Ch'ge.Sht.No.
(UNLESS OTHERWISE SPECIFIED)RESISTORS = Ohms (
(
DIODES =
CAPACITORS = MFD
1A, 400V
VOLTAGE
1
SENSE
THE LINCOLN ELECTRIC CO.EQUIP.
CLEVELAND, OHIO U.S.A.
332
R7
10 PIN REMOTE
OPTIONAL
J
A
10K
POT
GND
C
D
FILE: M17609_1BA
UNLESS OTHERWISE SPECIFIED) LABELS.022/50V
1/4W
STT REMOTE PROTECTION BOARD
3
ON 2 PLACE DECIMALS IS + .O2
DR.WITH PUBLISHED STANDARDS
FEEDER AMPHENOL
N
42 VAC
MSHT.NO. M
SCHEMATIC
EARTH GROUND CONNECTION
17609MLD CHK.
SCALE
POT
INTERFACE
10K
REMOTE
PB
COMMON CONNECTION
VOLTAGE NET
FRAME CONNECTION
POWER SUPPLY SOURCE POINT
J343
J331
17609
I
E
J347
J363
J374
J372
J342
M
AMPHENOL
.39mH
L1
7
2
I
K
8
C- 16
TRIGGER
BG
GND
SUP'S'D'G.
C
0
115 VAC
SUPPLY
LAST NO. USED
D-
R-
42
H
F
TRIGGER
41
B
31
A
J
L-
TP- 3
32
21
B
G
D
14 PIN WIRE
G
F
E
M
H
L
4
F.V.
5-19-95
ELECTRICAL DIAGRAMS
INVERTEC STT & STT II
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urn
toS
ectio
nTO
CR
etur
nto
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tion
TOC
Ret
urn
toS
ectio
nTO
CR
etur
nto
Sec
tion
TOC
Ret
urn
toM
aste
rTO
CR
etur
nto
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ter
TOC
Ret
urn
toM
aste
rTO
CR
etur
nto
Mas
ter
TOC
PC Board Assembly - Remote Protection - All Codes - (L9657)
NOTE: Lincoln Electric assumes no responsibility for liablilities resulting from board level troubleshooting. PC Board repairs will invalidate your factory warranty. Individual Printed Circuit Board Components are not available from Lincoln Electric. This information is providedfor reference only. Lincoln Electric discourages board level troubleshooting and repair since it may compromise the quality of the design and may result in danger to the Machine Operator or Technician. Improper PC board repairs could result in damage to the machine.
G-29G-29