Safety Depends on YouLincoln 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 before youact and be careful.
For use with machines having Code Numbers: 9218921992209383981098119812
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101481014910150105561055710558
• World's Leader in Welding and Cutting Products •
• Sales and Service through Subsidiaries and Distributors Worldwide •
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 welding arc
or when the engine is running. Stop the engine andallow it to cool before refueling to prevent spilledfuel from vaporizing on contact with hot engineparts and igniting. Do not spill fuel when filling tank.If fuel is spilled, wipe it up and do not start engineuntil fumes have been eliminated.
____________________________________________________1.d. Keep all equipment safety guards, covers and devices in position and
in good repair.Keep hands, hair, clothing and tools away from V-belts,gears, fans and all other moving parts when starting, operating orrepairing 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 or idler by push-ing on the throttle control rods while the engine isrunning.
___________________________________________________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. KEEPCHILDREN 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 you purchase a copy of “Safety inWelding & Cutting - ANSI Standard Z49.1” from the American Welding Society, P.O. Box 351040, Miami, Florida 33135 or CSA Standard W117.2-1974. AFree copy of “Arc Welding Safety” booklet E205 is available from the Lincoln Electric Company, 22801 St. Clair Avenue, Cleveland, Ohio 44117-1199.
BE SURE THAT ALL INSTALLATION, OPERATION, MAINTENANCE AND REPAIR PROCEDURES ARE PERFORMED ONLY BY QUAL-IFIED 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 cancer,birth defects, and other reproductive harm.
The engine exhaust from this product contains chem-icals known to the State of California to cause cancer,birth defects, or other reproductive harm.
The Above For Diesel Engines The Above For Gasoline Engines
LN-25
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iiSAFETYii
ARC RAYS can burn.4.a. Use a shield with the proper filter and cover
plates 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-free glovesto 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.
Replace damaged 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 voltage ofboth 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. 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 to formphosgene, a highly toxic gas, and other irritating products.
5.c. 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.d. 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.e. Also see item 1.b.
Mar ‘95
LN-25
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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.
iiiSAFETYiii
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 passing through lift-ing chains, crane cables or other alternate circuits. This can cre-ate fire hazards or overheat lifting chains or cables until they fail.
6.h. Also see item 1.c.
LN-25
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ivSAFETYiv
PRÉCAUTIONS DE SÛRETÉPour votre propre protection lire et observer toutes les instructions etles précautions de sûreté specifiques qui parraissent dans ce manuelaussi bien que les précautions de sûreté générales suivantes:
Sûreté Pour Soudage A L’Arc1. Protegez-vous contre la secousse électrique:
a. Les circuits à l’électrode et à la piéce sont sous tension quandla machine à souder est en marche. Eviter toujours tout con-tact entre les parties sous tension et la peau nue ou les véte-ments mouillés. Porter des gants secs et sans trous pour isol-er 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 l e spositions assis ou couché pour lesquelles une grande partiedu 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 tension desporte-électrodes connectés à deux machines à souder parceque la tension entre les deux pinces peut être le total de la ten-sion à vide des deux machines.
f. Si on utilise la machine à souder comme une source de courantpour soudage semi-automatique, ces precautions pour leporte-électrode s’applicuent aussi au pistolet de soudage.
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 rayonnementde l’arc et des projections quand on soude ou quand onregarde l’arc.
b. Porter des vêtements convenables afin de protéger la peau desoudeur et des aides contre le rayonnement de l‘arc.
c. Protéger l’autre personnel travaillant à proximité au soudage àl’aide d’écrans appropriés et non-inflammables.
4. Des gouttes de laitier en fusion sont émises de l’arc de soudage.Se protéger avec des vêtements de protection libres de l’huile, telsque les gants en cuir, chemise épaisse, pantalons sans revers, etchaussures montantes.
5. Toujours porter des lunettes de sécurité dans la zone de soudage.Utiliser des lunettes avec écrans lateraux dans les zones où l’onpique 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 de lamasse. Un court-circuit accidental peut provoquer un échauffe-ment et un risque d’incendie.
8. S’assurer que la masse est connectée le plus prés possible de lazone de travail qu’il est pratique de le faire. Si on place la massesur la charpente de la construction ou d’autres endroits éloignésde la zone de travail, on augmente le risque de voir passer lecourant de soudage par les chaines de levage, câbles de grue, ouautres circuits. Cela peut provoquer des risques d’incendie oud’echauffement des chaines et des câbles jusqu’à ce qu’ils serompent.
9. Assurer une ventilation suffisante dans la zone de soudage. Ceciest particuliérement important pour le soudage de tôles gal-vanisées plombées, ou cadmiées ou tout autre métal qui produitdes fumeés toxiques.
10. Ne pas souder en présence de vapeurs de chlore provenantd’opérations de dégraissage, nettoyage ou pistolage. La chaleurou les rayons de l’arc peuvent réagir avec les vapeurs du solvantpour produire du phosgéne (gas fortement toxique) ou autres pro-duits irritants.
11. Pour obtenir de plus amples renseignements sur la sûreté, voir lecode “Code for safety in welding and cutting” CSA Standard W117.2-1974.
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 dispositif demontage ou la piece à souder doit être branché à une bonne miseà 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 debrancher àl’interrupteur à la boite de fusibles.
4. Garder tous les couvercles et dispositifs de sûreté à leur place.
• Turn off power source beforeinstalling or servicing.
• Do not touch electricallyhot parts.
• Turn the input power to thewelding power source off at thefuse box before working in theterminal strip.
• Only qualified personnel shouldinstall, use or service thisequipment.
DC-250
a. Connect a jumper from 2 to 4 on the power sourceterminal strip so the output will be energized whenthe DC-250 is turned on.
b. Connect electrode cable to the “Innershield/GMAW” output terminal of polarity required byelectrode. Connect work lead to other“Innershield/GMAW” output terminal.
c. Place “Set to CV Electrode Cable Polarity” switchat appropriate position.
d. Place power source toggle switch in “OutputControl at DC-250” position, unless a RemoteControl is connected to 75, 76 and 77 on the DC-250 terminal strip.
e. Place mode switch in “Innershield GMAW (CV)”position. Set CV arc control to “2” (or “NORMAL”on some machines). Init ial ly set the outputcontrol on “7”.
DC-400 AND CV-400
a. Connect a jumper from 2 to 4 on the powersource terminal strip so the output wil l beenergized when the power source is turned on.
NOTE: DC-400 machines above Code 9200 havean output toggle switch to perform this function.
b. Connect the electrode cable to the outputterminal of polarity required by electrode.Connect work lead to other output terminal.
SAFETY PRECAUTIONS
Unless an optional output control or contactor is usedwith the LN-25, the electrode circuit (including weldingwire, wire drive and welding gun) is electrically hotwhen the welding power source is on. The gun triggercontrols wire feed only.
Disconnect or shut off welding power source beforemaking connections or installations to the LN-25.
Welding gun should be stored in the insulatedgun holder, located near the rear on the top of theLN-25 case, to avoid accidental arcing. The LN-25should be positioned upright on a horizontal surface.
ELECTRIC SHOCK can kill.
• Do not touch metal portionsof the LN-25 lead clip whenwelding power source is on.
POWER SOURCE CONNECTION
The LN-25 can be used with any DC welding powersource. A constant voltage power source isrecommended; however, the LN-25 can also be usedwith a constant current power source as long as theopen circuit voltage is less than 110V DC.
Do not use LN-25 models below Code 9200 with anyTIG or Square Wave welding power sources. Do notuse LN-25 models equipped with internal contactorswith non- Lincoln TIG or Square Wave welding powersources. Damage to the LN-25 circuit can occur as aresult of the high output inductance typicallyassociated with these power sources. TIG highfrequency power should never be applied to the LN-25.
If not using an LN-25 Remote Output Control option(See Remote Output Control Options and CableAssemblies Section), the power source output mustbe electrically “hot” at all times when the powersource is turned on.
See the power source instruction manual for properpower source connections and setting required.
WARNING
WARNINGWARNING
CAUTION
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INSTALLATION A-4
LN-25
A-4
c. Place “Set to Same Polarity As Electrode CableConnection” switch at appropriate position.
d. Place power source toggle switch in “OutputControl at DC(CV) -400” position, unless a remotecontrol is connected to 75, 76 and 77 on thepower source terminal strip or to the MS typeconnector.
e. If power source has a mode switch, set switch toConstant Voltage Innershield. Initially set theoutput control on “6”.
DC-600
a. Connect a jumper from 2 to 4 on the power sourceterminal strip so the output will be energized whenthe DC-600 is turned on. (For DC-600 belowCode 8200, also jumper N to S.)
b. Connect the electrode cable to the output terminalof polarity required by electrode. Connect worklead to other output terminal.
c. Place “Set to Same Polarity As Electrode CableConnection” switch at appropriate position.
d. Place power source toggle switch in “OutputControl at DC-600” position, unless a remotecontrol is connected to 75, 76 and 77 on the DC-600 terminal strip.
e. Set mode switch to Constant Voltage Innershield.Initially set output control on “4”.
SAM-400, –650
a. Connect a jumper from 2 to C4 on the powersource terminal strip so the output wil l beenergized when the SAM power source is on.
b. Connect work lead to WORK stud. Connectelectrode to AUTO EQUIPMENT stud. ConnectSAM-650 “Tap” lead to the Innershield studdesired.
c. Set ELECTRODE POLARITY switch to constantvoltage polarity required by electrode.
d. Set toggle switch to “Constant Voltage” and setthe Constant Voltage Control on welder and theportable field control on #5 for initial start.
SA-200, –250 OR SAE-300, –400 (WITHCV ADAPTER)
a. For electrode negative welding, connect theelectrode lead from the LN-25 to the outputterminal on the CV Adapter, and the work lead tothe power source output terminal labeled
“POSITIVE”. For electrode positive welding,interchange the above lead connections so theLN-25 electrode lead is then connected to thepositive power source terminal.
b. Place both switches on the CV Adapter to the CVINNERSHIELD position and make appropriatepower source settings per the CV Adapter instruc-tions provided for the power source being used.
c. The output voltage is set with the voltage controlon the CV Adapter.
NOTE: Refer to the Instruction Manual provided withthe machine for details on connection and operationof the LN-25 with the power source.
INVERTEC, CV300 AND OTHER NEWERLINCOLN POWER SOURCES
Refer to the instruction manual provided with thepower source for details on connection and operationof the LN-25 with these newer machines.
GUN CABLE CONNECTION TOFEEDER
Lay the cable out straight. Insert the connector on thewelding conductor cable into the brass conductorblock on the front of the wire drive unit. Make sure it isall the way in and tighten the hand wheel clamp. Keepthis connection clean and bright. Connect the controlcable polarized amphenol plug into the mating 5-cavityreceptacle on the front panel of the wire feeder case.
FOR GMA GUN AND CABLES:
Requires installation of K430-1 or K430-2 GasSolenoid Kit (factory installed on K446 and K449models).
See K430-1 or K430-2 Gas Solenoid Kit Section (inAccessories Section) for gas solenoid operation andgas supply connection.
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INSTALLATION A-5
LN-25
A-5
Install the barbed fitting and union nut to the 5⁄8-18female inert gas fitting on the front panel of the LN-25 case. Connect the 3⁄16" I.D. gas hose from the guncable to the barbed fitting.
When the gun is to be removed, this fitting can beeasily detached by loosening the union nut.
WELD CABLE CONNECTION
The size of the electrode cable and work cable mustbe sufficient for the maximum weld current and totalcable length to be used. Refer to table A.1.
On units without an internal contactor route theelectrode cable through the oval hole in the LN-25 rearpanel, then along the case floor behind the reelsupport and around the door side of the wire drive.Connect the electrode cable to the LN-25 using the1⁄2" bolt on the front of the wire drive.
On units with an internal contactor connect theelectrode cable to the LN-25 electrode input cable withthe nut and bolt provided. Tape the bolted connection.
ELECTRODE CABLE CONNECTION(FOR LATER CODE NUMBERS ABOVE 10500)
Route the electrode cable through the oval holein the lower port ion of the LN-25 rear panel.Connect the electrode cable to the LN-25 inputstud using the the 1/2” nut provided.
Secure the cable with the strain rel ief c lampprovided. All units are supplied with an optionalpigtail for customers that prefer to make a tapedand bolted connection externally.
WORK CABLE CONNECTION
Connect a work lead of sufficient size between theproper output stud on the power source and thework. Be sure the connection to the work makest ight meta l - to-meta l e lect r ica l contact . Poorwork lead connections can result in poor weldingperformance.
WIRE FEED DRIVE ROLL ANDGUIDE TUBE KITS
Turn off power source before installing or changingdrive roll and/or guide tubes.
NOTE: The maximum wire sizes the LN-25 willsatisfactorily feed are 5⁄64" cored and 1⁄16" solidelectrodes.
The electrode sizes that can be fed with each roll andguide tube are stencilled(1) on each part. Check the kitfor proper components. See the instructions, includedwith the drive roll kit, to install these parts on newmachines or replace them on used machines. Referto table A.2.
Steel(Can also be used for .052).045 and .052 Solid Steel -.052.045 and .052 Cored -.052C.035 Solid Steel -.035S.035 Cored -.035C.030 Solid Steel -.030S.025 Solid Steel -.025S
• Do not touch electrically livepart or electrode with skin orwet clothing.
• Insulate yourself from workand ground.
• Always wear dry insulatinggloves.
ARC RAYS can burn.
• Wear eye, ear and body pro-tection.
FUMES AND GASSES canbe dangerous.
• Keep your head out offumes.
• Use ventilation or exhaust toremove fumes from breath-ing zone.
WELDING SPARKS cancause fire or explosion.
• Keep flammable materialaway.
WARNING
GENERAL DESCRIPTION
The LN-25 is a lightweight portable semiautomaticwire feeder designed for “across-the-arc” operationwithout a control cable on most any DC welding powersource. Simply connect the LN-25 to the electrodecable, clip it to Work and it is ready to weld, using upto 30 lb. coils or spools.
The wire drive, controls and wire reel are fullyenclosed in a rugged molded plastic case providing acompact and versatile welding package ideally suitedto “on-the-go” field welding applications in virtually anyenvironment.
RECOMMENDED PROCESSESAND EQUIPMENT
When combined with the drive roll kits andaccessories available for use with the LN-25, aversatile portable welding system can be provided tomeet the specific needs of Innershield, submerged arcor gas metal arc welding applications within the wirefeed capabilities of the LN-25.
The LN-25 provides constant wire feed speed for usewith constant voltage (CV) power sources, and arc-sensing wire feed speed for use with constant current(CC) (formerly variable voltage) power sources. Wirespeed is presettable on a dual-range calibrated dial.
The power sources recommended for use with the LN-25 include the DC-250, -400, -600, CV-400 and R3Stype transformer machines, and the SAM-400, -650engine welders, as well as the SA-200, -250 or SAE-300, -400 with CV Adapter and Pulse Power 500 withK460-1 LN-25 Kit.
WELDING CAPABILITY
The LN-25 will handle up to 500 Amp 60% duty cyclewelding currents. However, when equipped with aK443-1 or K443-2 (depending on code number)Contactor, the LN-25 will handle up to 300 Amp 60%duty cycle.
SAFETY PRECAUTIONS
READ AND UNDERSTAND ENTIRE SECTION
BEFORE OPERATING MACHINE
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OPERATION B-3B-3
LN-25
VOLTMETER
(Factory installed on model Codes above 9218)
The 40V DC analog voltmeter is mounted to the frontcontrol panel of the LN-25 and is connected to readthe arc voltage between the LN-25 electrode cableconnection and the work clip lead.
NOTE:
1. The Voltmeter will read zero if the LN-25 work cliplead is not connected to work, even if the elec-trode is electrically “hot” to work.
2. The Voltmeter will read below zero if the LN-25polarity switch is not set to the same polarity asthe electrode.
3. The Voltmeter will read power source open circuitvoltage when the gun trigger is open, even if theLN-25 is equipped with the internal contactor.
“ELECTRODE POLARITY” SWITCH
The polarity switch is located on the front panel of theLN-25 case.
Set the switch to the same polarity as the electrodelead connection to the power source. If the switch isnot set for the correct polarity, the wire feeder will notoperate.
WIRE FEED MODE SWITCH
The CV-VV (CC) Wire Feed Mode switch is locatedinside the LN-25 case. The toggle switch extends frombeneath the control box just above the wire drive.
The forward “CV” position provides constant wire feedspeed mode for use with constant voltage (CV)welding power sources.
The backward “VV (CC)” position provides arc-sensingwire feed speed mode for use with constant current(formerly variable voltage) welding power sources.
WIRE SPEED DIAL AND RANGE SWITCH
The Wire Speed control dial on the front panel of theLN-25 has two calibrated dial ranges selected by theHI-LO Dial Range switch.
When switched to the LO range position, the constantwire feed speed (CV Wire Feed Mode) is set on theinside (white) dial range calibrated for 50 to350 in/min.
When switched to the HI range position, the constantwire feed speed (CV Wire Feed Mode) is set on theoutside (black) dial range calibrated for 50 to700 in/min.
The volts marks around the HI range calibrated dialindicate the minimum arc volts required to obtain theindicated HI range wire feed speeds. For example; ifwire speed is set to 400 in/min., a welding procedure
LN-25 INSTRUMENTS ANDCONTROLS
Refer to Figure B.1 for control locations.
REMOTEARC VOLTAGE
CONTROL(OPTIONAL)
WIRE SPEEDDIAL RANGE
SWITCH
WIRESPEEDDIAL
VOLTMETER
WORK CLIPLEAD
GUNCONNECTION
BLOCKGUN
TRIGGERAMPHENOL
CONNECTOR
GASFITTING
(OPTIONAL)
ELECTRODEPOLARITYSWITCH
GAS POST/PRE FLOW
TIMERS(OPTIONAL)
ELECTRODECABLE
OPTIONALGAS INPUT
FITTING
GAS PURGEBUTTON
FIGURE B.1 – CONTROL LOCATIONS.
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OPERATION B-4B-4
LN-25
arc voltage of at least 17V would be required to obtainthe 400 in/min. wire feed speed.
WORK CLIP LEAD
IMPORTANT SAFETY NOTE: To avoid possibleelectrical shock, do not touch the metal portions ofthe LN-25 work lead clip if the power source output ison. The clip will be electrically “HOT” to work if theinput electrode cable to the LN-25 is electrically “HOT”even if the gun trigger is off and even if an internalcontactor is used. Care should be taken to only handlethe LN-25 work clip by its non-metal insulated portionsand/or the welding power source should be turned offbefore handling the work clip.
The 15 ft work clip lead attached to the front panel ofthe LN-25 case must be connected directly to the workusing the spring clip on the end of the lead.
If not connected, the LN-25 will not operate even ifa K431-1 or K624-1 (42V) Remote Output Controloption (refer to Accessories Section) is used.However, the electrode will still be electrically “HOT”when the clip lead is disconnected, if K431-1 orK624-1 (42V) Remote Output Control Option, orInternal Contactor (K443-1), is not used.
NOTE: The clip lead also serves as a work sensinglead for the LN-25 Voltmeter (if installed). If the cliplead is extended by the user beyond the standard 15ft. length, the voltmeter reading will be lower than theactual arc volts due to the LN-25 motor control cur-rent flowing through the resistance of the extendedlead. To minimize this voltmeter error, the followingminimum lead size is recommended for the maximumextended lengths shown:
AWG Maximum Length
#14 25 Ft#12 50 Ft#10 100 Ft#6 200 Ft
REMOTE ARC VOLTAGE CONTROL (OPTIONAL)
This rheostat control allows you to control the powersource output arc voltage level. Refer to K444, K444-1and K444-2 Remote Voltage Kits in the Accessoriessection.
GAS FITTING (OPTIONAL)
Provides gas output connection to the welding gun forthe GMAW process. Refer to K430-1 Gas Solenoid Kitin the Accessories Section.
GAS POST PRE-FLOW TIMERS (OPTIONAL)
Allows for variable adjustment of gas pre-flow & post-flow at the start and end of the weld. Refer to K434-1 Gas Flow Timer Kit in Accessories Section.
WARNING
WARNING
ELECTRIC SHOCK can kill.
• Do not touch metal portionsof the LN-25 lead clip whenwelding power source is on.
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OPERATION B-5B-5
LN-25
g. To remove Readi-Reel from Adapter, depress re-taining spring tab with thumb while pulling theReadi-Reel cage from the molded adapter withboth hands. It is not necessary to remove adapterfrom spindle.
h. Load wire into wire drive per Loading Wire DriveSection.
MOUNTING 10 TO 30 LB SPOOLS
For 12" Diameter Spools:
a. Remove the locking collar and the Readi-Reeladapter shipped on the 2" diameter spindle(adapter is not required).
b. Place the spool on the spindle so the brakeholding pin enters one of the holes in the backside of the spool. Be sure the wire comes off thespool in a clockwise direction when dereeled fromthe bottom of the coil.
c. Replace and tighten the locking collar.
d. See Loading Wire Drive section for loadinginstructions.
For 8" Diameter Spools (Requires optional K468Spindle Adapter for 8" Spools):
a. Remove the locking collar and the Readi-Reeladapter shipped on the 2" diameter spindle(adapter is not required).
b. Slide S18221 Spindle Adapter onto the 2" spindleso the brake holding pin enters the adapter pinhole.
c. Place the spool on the spindle so the adapter tabenters one of the holes in the back side of thespool. Be sure the wire comes off the spool in aclockwise direction when dereeled from thebottom of the coil.
d. Replace and tighten the Locking Collar.
e. Load wire into wire drive per Loading Wire DriveSection.
MOUNTING 13 OR 14 LB INNERSHIELD COILS(Requires Optional K435 Spindle Adapter for 14 lbCoils.)
a. Remove the locking collar and the Readi-Reeladapter shipped on the 2" diameter spindle(adapter is not required).
b. Mount K435 Spindle Adapter and Innershield coilper the Instructions (S18256) included with theK435.
LOADING ELECTRODE
MOUNTING 22 TO 30 LB READI-REEL® COILS
The early models of the LN-25 were factory equippedwith a K363-P Readi-Reel® Adapter which is requiredto load Lincoln 22 to 30 lb Readi-Reel coils. Latermodels require the optional K363-P adapter kit.
a. Make certain that the threaded locking collar ist ight and securely locks the adapter on thespindle (See Figure B.2).
b. Rotate the spindle and adapter so the retainingspring is at the 12 o’clock position.
c. Position the Readi-Reel so that it will rotate in aclockwise direction when feeding (wire is to bedereeled from bottom of the coil).
d. Set one of the Readi-Reel inside cage wires onthe slot in the retaining spring tab.
e. Lower the Readi-Reel to depress the retainingspring and align the other inside cage wires withthe grooves in the molded adapter.
f. Slide cage all the way onto the adapter until theretaining spring “pops up” fully.
Check to be sure the retaining spring has fullyreturned to the locking position and has securelylocked the Readi-Reel cage in place. Retaining springmust rest on the cage, not the welding electrode.
WARNING
WARNINGELECTRIC SHOCK can kill.
• Unless an optional outputcontrol or internal contactor isused with the LN-25, theelectrode circuit is electrically“Hot” when the power sourceis on.
• Turn off the power sourcewhile mounting electrodecoils.
SEQUENCE OF OPERATION
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OPERATION B-6B-6
LN-25
LOADING WIRE DRIVE
a. Turn the reel or spool until the free end of theelectrode is accessible.
b. While tightly holding the electrode, cut off the bentend and straighten the first six inches. Cut off thefirst inch. (If the electrode is not properlystraightened, it may not feed or may not go intothe outgoing guide tube causing a “birdnest”.)
c. Insert the free end through the incoming guidetube to the drive roll.
d. Turn on the welding power source.
Unless an optional output control or internal contactoris used with the LN-25, the electrode circuit iselectrically “hot” when the power source is on.
e. Press the gun trigger and push the electrode untilit just enters the drive roll.
When inching with gun trigger, the electrode and drivemechanism are always “hot” to work and ground. Usethe “cold” inch switch on models with internalcontactor.
f. Inch the electrode through the gun.
g. Adjust the brake tension with the thumbscrew onthe spindle hub until the reel turns freely, but withlittle or no overrun when wire feeding is stopped.Do not over tighten.
Keep gun in LN-25 gun holder when not feeding wireto prevent accidental arcing.
IDLE ROLL PRESSURE SETTING
The idle roll pressure is set at the factory backed outtwo turns from full pressure. This is an approximatesetting. For small wire sizes and aluminum wire, theoptimum idle roll pressure varies with type of wire,surface condition, lubrication and hardness. The op-timum idle roll setting can be determined as follows:
1. Press end of gun against a solid object that iselectrically isolated from the welder output. Pressthe gun trigger for several seconds.
2. If the wire “birdnests,” jams or breaks at the driveroll, the idle roll pressure is too great. Back thepressure setting out 1⁄2 turn, run new wire throughgun, and repeat above steps.
3. If the only result is drive roll slippage, shut off thepower source, then loosen the gun cable clamping
WARNING
WARNING
CAUTION
2" O.D.SPINDLE
MOLDED ADAPTER
RETAININGSPRING
BRAKE HOLDING PIN(MUST ENGAGE HOLE
IN ADAPTER RIB)
GROOVES
READI-REEL
INSIDE CAGEWIRES
THREAD LOCKINGCOLLAR
FIGURE B.2 – READI-REEL INSTALLATION.
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OPERATION B-7B-7
LN-25
screw in the gearbox conductor block and pull thegun cable forward about six inches. There shouldbe a slight waviness in the exposed wire. If thereis no waviness, the pressure is too low. Increasethe pressure setting 1⁄4 turn, lock the gun cable inplace and repeat the above steps.
The LN-25 permits accurate presetting of the desiredwire feed speed, before welding, in both CV and CCwire feed modes.
SETTING CONSTANT WIRE FEED SPEED (CVMODE)
a. Set Wire Feed Mode switch to CV position.
b. Set Dial Range switch to LO position for wire feedspeeds up to 350 in/min., or HI position for wirefeed speeds over 350 in/min.
c. Set Wire Feed dial to the desired wire feed speedon the selected calibrated dial range.
The wire speed will remain constant at the value set,independent of arc voltage changes, as long as thearc voltage does not drop below the value per thechart below for the max. wire feed speed shown:
When using a constant current (formerly variablevoltage) power source, welding performance is im-proved using arc sensing wire feed speed (CC [VV]mode). In this wire feed mode the wire speedincreases if arc voltage increases, and decreases ifarc voltage decreases, but remains constant at anyspecific voltage level.
The LN-25 permits accurate CC mode presetting ofthe desired wire feed speed, for the desired arcvoltage to be used, by setting the Wire Speed dial inthe following manner before welding:
a. Set Wire Feed Mode switch to CC position.
b. Referring to the graph located above the Modeswitch (also shown in Figure B.3):
1. Select the horizontal line representing the DE-SIRED IN/MIN. for the welding procedure. (Seeexample arrow line for 375 in/min.)
2. Select the diagonal line representing the ARCVOLTS to be used for the welding procedure.(See example arrow line for 29 volts.)
3. Determine the vertical line representing the CCWIRE SPEED SETTING where the above twolines cross. (See example arrow line for 450.)
c. Set the Wire Speed dial to the value determinedin Step (3) above (450 for example used). Use HIDial Range if value to be set is over 350.
The wire will feed at the DESIRED IN/MIN speedwhen the welding power source is set to the arcvoltage to be used for the weld procedure (375 in/min.at 29V for example used).
A chart representation of the CC wire speed settinggraph is shown in Figure B.4, giving the Wire Speeddial setting required for the DESIRED IN/MIN and ARCVOLTS used for the welding procedures:
a. Connect work cable to metal to be welded. Workcable must make good electrical contact to thework. The work must also be grounded as statedin “Arc Welding Safety Precautions.”
b. Check that the LN-25 is properly connected to thepower source for the polarity and process to beused, and appropriate power source settings aremade for the procedure to be used. (Refer topower source operating and connectioninstructions.)
NOTE: If the K431-1 Remote Output Control Kit orK624-1 42V Remote Control Module is installed butthe LN-25 is to be used without the Remote ControlCable Assembly, then the Remote Board harness plugmust be removed from the 16-pin receptacle on theControl Board and the jumper plug (T13498-21)reinstalled.
c. Place the LN-25 conveniently near the work areain a location to minimize exposure to weld spatterand to avoid sharp bends in the gun cable.
d. Connect the LN-25 Clip Lead to work and set Po-larity Switch to same polarity as electrode.
e. Set WIRE FEED MODE switch to CV or VV (CC),as appropriate for the power source, then set theproper DIAL RANGE and WIRE SPEED dial set-t ing for the proper wire feed speed per thewelding procedure:
For CV: Set dial to the calibrated IN/MIN desired.(Refer to Setting Constant Wire Feed SpeedSection.)
For CC: Set dial to value determined from the CCWire Speed Graph for the DESIRED IN/ MINand ARC VOLTS to be used. (Refer to SettingArc Sensing Wire Feed Speed Section.)
NOTE: If procedure permits a range of acceptablearc voltage, use the middle of the range todetermine proper WIRE SPEED setting.
f. If using the optional Gas Flow Timer, set the de-sired PREFLOW TIME and POSTFLOW TIME.
g. Be sure the proper contact tip for the wire sizebeing used is in the gun, and the gun is safefrom work contact. (Use the LN-25 insulatedgun holder.)
VV(CC) Speed Setting = Desired IPM X 35Arc Volts
FIGURE B.4 – VV (CC) WIRE SPEED SETTING.
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OPERATION B-9B-9
LN-25
ARC RAYS can burn.
• Do not touch metal portionsof the LN-25 lead Clip whenwelding power source is on.
CYLINDER may explode ifdamaged.
• Keep cylinder upright andchained to support.
• Keep cylinder away fromareas where it may be dam-aged.
• Never lift welder with cylinderattached
• Never allow welding elec-trode to touch cylinder.
• Keep cylinder away fromwelding or other live electricalcircuits.
h. Turn on the welding power source, as well as theshielding gas supply (if used).
Unless an optional output control or internal contactoris used, the electrode is electrically “hot” when thepower source is on. The gun trigger controls wirefeed only.
a. Cut the electrode within approximately 3⁄8" of theend of the contact tip for solid wire and withinapproximately 3⁄4" of the extension guide for coredwire.
b. Position electrode over joint. End of electrodeshould be slightly off the work.
WARNING
WARNING
WARNING
OPEN ARC WELDING WITH ACONSTANT CURRENT (formerlyvariable voltage) POWERSOURCE
Although a constant voltage (CV) power sourceis recommended for Innershield® and gas metalarc (GMAW) open arc welding, satisfactory generalpurpose welding may be obtained using theLN-25 with a constant current (CC) power sourcefor non-critical commercial quality mild steelwelding applications.
PROCEDURE AT END OF COIL
When the wire on the reel is used up, the followingprocedure is to be followed for removing the old wirefrom the gun cable and loading a new reel.
a. Shut off power source if a Remote Output ControlOption or internal contactor is not used.
b. Cut the end of the electrode off at the gun end.Do not break it off by hand since this puts a slightbend in the wire and makes it diff icult orimpossible to pull it back through the nozzle.
c. Uncoup le t he gun conduc to r cab le f r omthe LN-25.
d. Lay the cable out straight.
e. Using pliers to grip the wire, pull it out of thecable from the connector end. Do not pull it fromthe gun end.
f. Put the conductor cable back on wire drive unitafter the electrode has been removed.
g. Load a new coil of wire and feed it through thecable as described in Loading Electrode Section.
c. Lower welding helmet, close gun trigger, andbegin welding. Hold the gun so the contact tip towork distance gives the correct electrical stickoutas required for the procedure being used.
NOTE: If the arc voltage is not within the properprocedure range adjust the power source outputcontrol. (The CC mode WIRE SPEED setting shouldnot be changed from the preset procedure value forthe proper arc voltage.)
d. To stop welding, release the gun trigger andthen pull the gun away from the work. Store thegun in the LN-25 insulated gun holder whennot welding.
WELDING
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OPERATION B-10B-10
LN-25
Do not use LN-25 models below Code 9200 with anyTIG or Square Wave welding power sources. Do notuse LN-25 models equipped with internal contactorswith non-Lincoln TIG or Square Wave welding powersources. Damage to the LN-25 circuit can occur asa result of the high output inductance typicallyassociated with these power sources. TIG highfrequency power should never be applied to theLN-25.
While welding with a continuously fed electrode, weldcurrent variations are continuously taking place. Thereare many causes for these variations, butpredominantly they occur due to changes in electricalstickout (operator hand movements, nozzle tip contactvariations, etc.) and the dynamic metal transfercharacteristics of the process or procedure beingused (short arc, globular transfer, etc.).
When using a CV power source, these currentvariations have essentially no effect on the weldingarc stability since CV power sources can provide awide range of weld current levels with virtually nochange in average arc voltage. These “flat slope” CVpower sources, therefore, provide the arc powerrequired to produce the best welding characteristicsand ease of operation for most open arc, constantwire feed speed, welding processes.
CC (formerly VV) power sources, on the other hand,permit the arc voltage to decrease with increases inwelding current. The output characteristics of thesepower sources can range from a “drooping slope,”which provide minor arc voltage changes with weldcurrent variations, to “steep slope” which providebroad voltage changes with only minor currentvariations. The steeper the slope the more difficult itbecomes to maintain arc voltage stability with aconstant wire speed open arc process.
To aid in stabilizing the arc voltage when welding onCC power sources the LN-25 is provided with a CCwire feed mode. This arc voltage sensing feed modedecreases (or increases) the wire speed when the arcvoltage decreases (or increases). However, if theelectrode shorts to the work, the arc voltage willessentially drop to zero and the short circuit currentsupplied by the CC power source may not provideenough power to re-establish the arc (especially withsteeper slope machines). Under this condition theLN-25 feeder will stop, as if the trigger was released,and not restart until the short has been opened.
Arc shorting is more difficult to avoid when usinga CC power source, and requires a more refinedoperator technique than when using a CV powersource. Improved performance can be obtainedon CC power source appl icat ions wi th in thefollowing guidelines:
1. Flatter slope power sources with higher arc force(short circuit current) will improve performanceover steep slope machines. The steeper theslope, the more crit ical i t is to hold properelectrode stickout to maintain arc stabil i ty.Welding techniques, such as weaving, will bemore difficult to control. Use the highest outputcurrent tap or setting capable of providing thevoltage adjustment required for the procedure.
2. Use spray or non-shorting small ball type transferprocesses at higher procedure voltage levels.Generally, open arc processes with procedurevoltage levels over 22 volts perform satisfactorily.Arc stability at procedure voltage levels below 22volts may be more difficult to control, with thegeneral exception of fine (.023–.035) solid steelelectrodes with Argon-rich shielding gas or NR-152and NR-211 Innershield.
CAUTION
AUTOMATIC PROTECTIONSHUTDOWN
The LN-25 control provides automatic electronicprotection circuits which shut down the LN-25 forexcessively high power source open circuit voltage orexcessive motor overload.
OVERVOLTAGE SHUTDOWN
If the power source open circuit voltage exceeds about110-120 volts, the LN-25 will not operate until thepower source voltage drops below about 102-110volts.
MOTOR OVERLOAD SHUTDOWN
If excessive motor overload occurs (due to prolongedexcessive feeding force, jammed drive rolls or shortedmotor leads), the LN-25 will shut down within a fewseconds after the overload occurs.
The shutdown will reset automatically when the guntrigger is released, but will reoccur if the overloadsituation is not remedied.
LN-25 OPTION CHARTO = CANNOT BE USED WITH X = REQUIRED ➀ = REQUIRES ONE OF THESE + = INCLUDED WITH
K430-2 or SolenoidK430-1 Kit X + +
Remote OutputK431-1 Control Module ➀ ➀ O X X O O O O O
RemoteK432 Control Cable X X
115VACK433 Power Source X X
Remote Box
Gas FlowK434-1 Timer Kit ➀ ➀ ➀ ➀
50 Ft.K439 Ext. Cable X
K443-2 or ContactorK443-1 Kit + O O
Remote for PowerK444 Source w/Terminal Strip ➀ ➀ ➀ O O
Remote for PowerK444-1 Source w/6 Pin Amphenol ➀ ➀ ➀ O O
Remote for PowerK444-2 Source w/14 Pin Amphenol ➀ ➀ ➀ O O
42VAC RemoteK-624-1 Output Control Module ➀ ➀ O O O O O O ➀ ➀ ➀
500 Amp Cable /w Stud-K625 Type Output Terminals X
350 Amp Cable /w Stud-K626 Type Output Terminals X
400 Amp Cable /w Twist-K627 Mate Type Terminals X
IMPORTANT SAFETY NOTE: This wire feeder provides “COLD” electrode when gun trigger is released ifequipped with K431-1, K432 or K433 remote output control system, or a K443-1or K443-2 internal contactor kit.This feature and the use of a DC Constant Voltage welder provide an added margin of safety when weldingmust be performed under electrically hazardous conditions such as:
• Damp locations • While wearing wet clothing • On metal structures, or, • In cramped positions (sitting, kneelingor lying) if there is a high risk of unavoidable or accidental contact with the workpiece or ground.
K42
8L
N-2
5
K44
6L
N-2
5K
449
LN
-25
K43
1-1
K43
2
K43
3
K44
3-1
K44
4
K44
4-1
K44
4-2
K62
4-1
K62
5
K62
6
K62
7
KIT
NO
.
How to use Table C.1.
Determine which Kit No. is to be used. Locate that Kit No. in the left hand vertical column.Scan horizontally to determine which LN-25 model is required and what additional kits may be required.
TABLE C.1
LN-25 MODELS LN-25 KITS
SEE TEXT
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ACCESSORIES C-3C-3
LN-25
OPTIONAL ACCESSORIES
ELECTRIC SHOCK can kill.
• Do not operate with coversremoved.
• Turn off power source beforeinstalling or servicing.
• Do not touch electrically hotparts.
• Turn the input power to thewelding power source off atthe fuse box before working inthe terminal strip.
• Only qualified personnelshould install, use or servicethis equipment.
GAS SOLENOID KIT (K430-2 FOR CODES
ABOVE 10500 OR K430-1 FOR CODES BELOW 10500)
(Factory Installed on K446 and K449 Models)
The kit permits the LN-25 to be used for Gas MetalArc Welding (GMAW) processes with a GMA guncable.
The kit can be used with or without a Remote OutputControl option installed in the LN-25 and provides flowof shielding gas:
1. With wire feed, when the gun trigger is closed.
2. Without wire feed, when the kit’s Purge button(located beneath the gas inlet fitting) is pressed.
NOTE: Always shut off the valve at the gas cylinderbefore making any gas connections to the LN-25.
User must provide a supply of shielding gas, a pres-sure regulator, a flow control valve and a hose fromthe flow valve to the gas inlet fitting of the LN-25.Install by connecting a supply hose from the gas flowvalve outlet to the 5⁄8-18 female inert gas fitting on theback panel of the LN-25 case. The LN-25 can be usedwith any shielding gas recommended in theelectrode’s product literature at a maximum pressureof 60 psi (4.1 bar). This may include gases such asArgon, Helium, Nitrogen and blended gases such asAr-He, Ar-N2, Ar-O2, Ar-CO2, CO2, Ar-CO2-O2.
See American National Standard Z-49.1, “Safety inWelding and Cutting” published by the AmericanWelding Society.
CYLINDER may explode ifdamaged.
• Keep cylinder upright andchained to support.
• Keep cylinder away fromareas where it may be dam-aged.
• Never lift welder with cylinderattached.
• Never allow welding electrodeto touch cylinder.
• Keep cylinder away fromwelding or other live electricalcircuits.
See GMA Gun Cable Gas Connection.
Installation instructions are included with the kit.
K434-1 GAS FLOW TIMER KIT
(Requires either a K431-1 Remote Output Control Kit,K624-1 42V Remote Output Control Kit, or internalcontactor K443-1 or K443-2 installed in LN-25).
The K434-1 Gas Flow Timer Kit is used with theLN-25 Gas Solenoid when the LN-25 is equippedwith any of the Remote Output Control Options orinternal contactor.
T h i s k i t p r o v i d e s t h e f o l l o w i n g g a s f l o wtimer functions:
1. Preflow Control - Provides flow of shieldinggas to the work before the arc is established.The solenoid valve is energized immediatelywhen the gun trigger is closed, but the timedelay before the wire feeder and welding outputare energized is adjustable between at least0 to 1 second.
2. Postflow Control - Provides flow of shielding gasto the work after welding is stopped. Delay of theshut off of the solenoid valve after the gun triggeris released is adjustable between at least 0.5 to5 seconds.
Installation instructions are included with this kit.
WARNING WARNING
WARNING
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LN-25 CONTACTOR KIT (K443-2 FOR CODES
ABOVE 10500 OR K443-1 FOR CODES BELOW 10500)
(Factory installed in K449 Model.)
The internal contactor provides “cold” electrode untilthe gun trigger is pressed, and a fixed burnback timedelay to prevent electrode from sticking in the weldcrater when the trigger is released. The contactor israted for use up to 300 amps. A cold inch switchallows the wire to be loaded into the system withoutbeing electrically “hot”.
Installation Instructions are included with the kit.
NOTE: The K443-1 or K443-2 cannot be used withK431-1 or K624-1 Remote Output Control Kit. Ifremote voltage control is desired along with theinternal contactor, obtain a K444, K444-1 or K444-2Remote Voltage Control Kit.
REMOTE OUTPUT CONTROLOPTIONS AND CONTROL CABLEASSEMBLIES
Remote Output Control Options are available to pro-vide the LN-25 with the following additional features:
1. “Cold” electrode until the gun trigger is pressed,and a fixed burnback time delay to prevent elec-trode from sticking in the weld crater when thegun trigger is released.
2. Remote (10K ohm rheostat) control of powersource output arc voltage level.
K431-1 REMOTE OUTPUT CONTROLKIT
(For use with K432 Remote Control Cable and K433Power Source Remote Box.)
These kits can only be used with LN-25’s above Code9200 or with LN-25’s equipped with a G1757-3 (orhigher part number) Control PC board. To preventpossible damage to the LN-25 with internal contactor,do not connect to non-Lincoln TIG or Square Wavepower sources. TIG high frequency power shouldnever be applied to the LN-25.
ACCESSORIES C-4C-4
LN-25
The Kit includes a Remote PC board and controlcable receptacle which mount and connect inside theLN-25 control box per the Installation Instructions(M17584) included with the kit.
NOTE: If the K431-1 Remote Output Control Kit isinstalled but the LN-25 is to be used without the K432Remote Control Cable Assembly, then the RemoteBoard harness plug must be removed from the 12-pin receptacle on the Control Board and the jumperplug (T13498-21) reinstalled.
K433 POWER SOURCE REMOTE BOX
(Requires K431-1 Remote Output Control Kit installedin LN-25 using K432 Remote Control Cable.)
The Remote Box is designed to mount and connectto Lincoln Idealarc® semiautomatic power sources perthe Installation Instructions and power sourceconnection diagrams included with the kit.
The Remote Box provides the proper welding powersource control interface and isolated 24V AC inputsupply for the LN-25 equipped with the K431-1Remote Output Control Kit.
Remote Box requires 115V AC, 50/60 Hz input and awelding power source using a contact closure outputpilot circuit, as available on appropriate Lincoln weld-ing power sources.
K432 REMOTE CONTROL CABLEASSEMBLY
(Requires K431-1 Remote Output Control Kit installedin LN-25 and K433 Remote Box mounted to powersource with 115V AC auxiliary power.)
The K432 control cable assemblies include an elec-trode cable, rated for up to 500 amps 60% duty cycle,and a 6-conductor control cable with pin connectorson both ends. Available in 25, 50, 75 and 100 ft.lengths.
The cable assembly end with the socket pin connectorconnects to the LN-25 per the Instructions includedwith the K431-1 kit.
The cable assembly end with the male pin connectorconnects to the K433 and power source per the In-structions included with the K433 kit.
CAUTION
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ACCESSORIES C-5C-5
LN-25
K439 REMOTE EXTENSION CABLEASSEMBLY
The 50 ft. Extension cable assemblies are used to ex-tend the K432 Remote Control Cable Assembly whenlonger cable lengths are required.
Multiple K439 Extensions may be used, however, toprevent excessive weld cable voltage drops, the 500amp max. rating of the K432 should be reduced by atleast 50 amps for each K439 Extension used. Forexample, if three K439 Extensions are used (150 fttotal extension), the maximum welding current usedshould be less than 350 amps.
The K439 Extension cable end with the male pin con-nector connects to the K433 Remote Box and powersource per the Instructions included with the K433 kit.
The K439 Extension cable end with the socket pinconnector connects to the mating K432 cable end (ornext K439 Extension cable end). The electrode cablesare connected using the bolt and nut provided withthe K439 Extension. Properly insulate the bolted con-nection with electrical tape.
K624-1 42V REMOTE OUTPUTCONTROL MODULE
(For use with K625, K626, K627 RemoteControl Cable)
The Module includes a 42V Remote PC board andcontrol cable receptacle which mount and connectinside the LN-25 control box per the InstallationInstructions included with the kit.
NOTE: If the K624-1 42V Remote Output ControlModule is installed but the LN-25 is to be used withoutthe K625, K626 or K627 Remote Control CableAssembly, then the Remote Board harness plug mustbe removed from the 16-pin receptacle on the ControlBoard and the jumper plug (T13498-21) reinstalled.
K625, K626, K627 REMOTE CONTROLCABLE ASSEMBLY
(Requires K624-1 Remote Output Control Moduleinstalled in LN-25.)
The K625, K626, K627 control cable assembliesinclude an electrode cable and a 8-conductor controlcable:
The cable assembly end with the socket pin connectorconnects to the LN-25 per the Instructions includedwith the K624-1 Kit.
The cable assembly end with the male pin connectorconnects to the power source per the Instructionsincluded with the K624-1 kit.
K444, K444-1 OR K444-2 REMOTEVOLTAGE CONTROL KIT
(Not required if using K431-1 or K624-1 RemoteOutput Control Kit.
The Remote Voltage Control Kit provides remote (10Kohm rheostat) control of power source output arcvoltage level.
K444 connects to power sources with control terminalstrip connections for lead numbers 75, 76 and 77.
K444-1 connects to power sources with a 6-pin controlreceptacle.
NOTE: To use a K444-1 with power sources with onlya 14-pin control receptacle, a K864 Adapter is requiredto connect to K444-1 and if using a power sourcewithout an output control switch, a K484 Jumper Plugwill also be required to jumper the output pilot circuit(2-4).
K444-2 connects to power sources with a 14-pincontrol receptacle and provides a 2-4 jumper toactivate power source output.
Installation Instructions are included with the kit.
K363P READI-REEL ADAPTER KIT
Adapts Lincoln Redi-Reel coils of electrode 30 lb.(14kg) and 22 lb. (10kg) to a 2” (51mm) spindle.Durable molded plastic one piece construction.Designed for easy loading: adapter remains on spindlefor quick changeover.
• Turn off power source beforeinstalling or servicing.
• Do not touch electrically hotparts.
• Turn the input power to thewelding power source off atthe fuse box before workingin the terminal strip.
• Only qualified personnelshould install, use or servicethis equipment.
CIRCUIT PROTECTION ANDAUTOMATIC SHUTDOWN
CONTROL PC BOARD FUSE
On G1757-6 (or higher part no.) PC boards the 1⁄8 ampfuse was replaced with electronic protection for triggercircuit faults to electrode circuit.
On G1757-2 through -5 part no. PC boards, the 1⁄8 ampfuse interrupts the 500A lead to the trigger switch. OnG1757- 1 PC boards a 5 amp fuse was used tointerrupt the 667 lead. The LN-25 will not operate ifthe fuse is blown.
AUTOMATIC PROTECTION SHUTDOWN
(See Automatic Protection Shutdown Section.)
ADJUSTING SPEEDSENSOR MODULE
The LN-25 Speed Sensor Module is a three lead HallEffect switch device encased in an externally threadedhousing which is screwed into a mounting plate on themotor side of the wire drive gearbox.
Proper positioning of this module is critical to properoperation of the LN-25 wire feed speed control. If the
ROUTINE MAINTENANCE
DRIVE ROLLS AND GUIDE TUBES
After feeding every coil of wire, inspect the drive rollsection. Clean it as necessary. Do not use a solventfor cleaning the idle roll because it may wash the lu-bricant out of the bearing. The drive roll, idle roll andguide tubes are stamped with the wire sizes they willfeed. If a wire size other than that stamped on the rollsis to be used, the rolls and guide tubes must bechanged.
The drive rolls for .035 through .052 cored electrodeand 1⁄16 through 5⁄64 electrode have a double set of teethso they can be reversed for additional life. Drive rollsfor .023 through .052 solid electrode and aluminumsizes have no teeth but use two grooves so they alsocan be reversed for additional life.
See Wire Feed Drive Roll and Guide Tube Kits Sec-tion for roll changing instructions.
WIRE REEL SPINDLE
No routine maintenance required. Do not lubricatespindle.
WARNING
SAFETY PRECAUTIONS CONTROL BOX
Every six months open and inspect the control sec-tion. The accumulated dirt should be gently blown offall of the electrical components. Be sure the air thatis being used is dry. Check that lead plugs are securein their receptacles.
WIRE DRIVE MOTOR AND GEARBOX
Every year examine the gearbox. Paint the gear teethwith molydisulfide filled grease. Do not use a graphitegrease.
Check the motor brushes. Replace if they are worndown to 1⁄4’’ or less. When ordering feed motorbrushes, g ive a l l in format ion f rom the motornameplate.
GUN AND CABLE MAINTENANCE
See IM manual provided with the gun and cable as-sembly.
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MAINTENANCE D-3D-3
LN-25
device is not screwed in far enough, the LN-25 motorspeed could be unstable or run at full speed with nocontrol. If screwed in too far, it will rub a moving partinside the gearbox.
The module is properly mounted to the gearboxas shipped from the factory. If the device is everremoved or replaced, proper mounting technique is asfollows:
1. Be sure all power to the LN-25 is shut off at thepower source.
2. Check that the module mounting plate is screwedsecurely to the side of the gearbox. Refer to DriveMotor and Gearbox Replacement Procedureand access to the Hall Effect Module in theTroubleshooting and Repair Section.
3. Gently screw the module into the mounting plateuntil it just touches and stops against the rotatingpart inside the gearbox.
4. Back the module out 1⁄2 turn, then snug the modulelock nut without rotating the module position. Donot over tighten lock nut.
CALIBRATION OF LN-25 WIRESPEED DIAL
Calibration of the LN-25 Wire Speed dial is achievedby proper mounting of the dial knob to the speedpotentiometer shaft. Whenever the knob is removed,the dial is recalibrated as follows:
NOTE: Knob set screw does not seat on shaft flat.
1. Be sure the Wire Speed potentiometer mountingnut is securely t ightened, then rotate thepotentiometer shaft so its flat faces about to the100 mark on the LO range calibrated dial.
2. Set DIAL RANGE switch to LO and WIRE FEEDMODE switch to CV position.
3. Press gun trigger to feed wire and measurethe wire feed speed (IN/MIN) using a PortableDigital Wire Feed Speed Meter (Lincoln K283).Take at least two readings to assure repeat-able accuracy.
Feed Speed Meter (Lincoln K283). Take at leasttwo readings to assure repeatable accuracy.
Electrode will be electrically “hot”. Do not allow fedwire to contact any metal common with welding work.
An alternate means to measure wire feed speedis as follows:
a. Cut wire off at the end of the gun tip.
b. Press trigger to feed wire for exactly 30 seconds.
c. Cut fed wire off at the end of the gun tip andaccurately measure its length.
d. Multiply the measured length by 2 to obtainthe wire speed (IN/MIN).
e. Repeat above steps to assure repeatableaccuracy.
4. Carefully slip speed knob onto potentiometershaft so it points precisely to the wire speedmeasured in step 3, then secure the knob setscrew without disturbing the position. Recheck byrepeating step 3.
EARLY MODELS ONLY - LATER MODELS HAVE CIRCUITRYINCLUDED ON CONTROL BOARD
THEORY OF OPERATION E-2E-2
LN-25
GENERAL DESCRIPTION
The LN-25 is a portable semiautomatic wirefeeder designed to operate from a DC arc
voltage. It is designed for maximum versatility ina variety of field applications. It can be used withmost constant voltage or constant current DCpower sources without the need of a controlcable.
FIGURE E.2 – INPUT POWER CIRCUIT.
CONTROL CIRCUITOPERATION
INPUT POWER CIRCUIT
The DC arc voltage from the power source isapplied to the LN-25 through the electrode cableand work sensing lead. This DC voltage isconnected to the polarity switch, which allowsthe wire feeder to be used in either electrodepositive or electrode negative polarity. Thevoltage is then coupled to the voltmeter andcontrol board. A wire feed mode switch isincluded to give the user the capability of usinga constant voltage or, in some processes, aconstant current power source. See Figure E.2.
WELDING CURRENT CIRCUIT
The electrode voltage is also applied to theconductor block through a heavy currentcarrying cable. The welding gun cable isconnected to the conductor block. Thiscombination of welding cable, optional contactor,conductor block and gun cable constitute thewelding current path to the electrode wire. SeeFigure E.2.
NOTE: Unshaded areas of block logic diagrams are the subject of discussion.
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ELECTRODEINPUT CABLE
TO WORKSENSING LEAD
POLARITY
SWITCH
VOLTMETER
CONTROLBOARD
WIRE FEEDMODE SWITCH
SOLENOIDPC BOARD
GASSOLENOID
WIRE SPEEDCONTROL
RANGESWITCH
CONDUCTORBLOCK
MOTOR
HALLEFFECTMODULE
GUNTRIGGER
CONNECTOROPTIONALCONTACTOR
BOARD
COLDINCH
SWITCH
OPTIONALCONTACTOR
GUN CABLE
RPM FEEDBACK
ARMATURE VOLTAGE
EARLY MODELS ONLY - LATER MODELS HAVE CIRCUITRYINCLUDED ON CONTROL BOARD
THEORY OF OPERATION E-3E-3
LN-25
FEEDBACK AND CONTROLCIRCUITS
The combination of the range switch and wirespeed control provides a command voltage forthe control board. The hall effect moduletransforms the motor RPM to a digital voltagefrequency that is “fed back” to the control board.When operating in the constant voltage (CV)mode, the control board monitors the “feedbacksignal”, compares it to the command voltage anddelivers the appropriate armature voltage to thewire feed motor. In this manner, a constant wirefeed speed is maintained. See Figure E.3. Whenthe LN-25 is connected to a constant current(CC) power source, a variable wire feed speed
is desirable to compensate for the varying arcvoltages associated with the constant currentprocess. To accomplish this, the control boardmonitors the command voltage, the feedbacksignal from the hall effect module and the arcvoltage. These three factors are monitored andcompared, and then the appropriate armaturevoltage is applied to the wire feed motor.
TRIGGER CIRCUIT
When the gun trigger is closed, the control boardis “signaled” to apply armature voltage to thedrive motor and to activate any auxiliary circuitsthat may be incorporated within the LN-25. SeeFigure E.3.
FIGURE E.3 – CONTROL CIRCUITS.
NOTE: Unshaded areas of block logic diagrams are the subject of discussion.
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ELECTRODEINPUT CABLE
TO WORKSENSING LEAD
POLARITY
SWITCH
VOLTMETER
CONTROLBOARD
WIRE FEEDMODE SWITCH
SOLENOIDPC BOARD
GASSOLENOID
WIRE SPEEDCONTROL
RANGESWITCH
CONDUCTORBLOCK
MOTOR
HALLEFFECTMODULE
GUNTRIGGER
CONNECTOROPTIONALCONTACTOR
BOARD
COLDINCH
SWITCH
OPTIONALCONTACTOR
GUN CABLE
RPM FEEDBACK
ARMATURE VOLTAGE
EARLY MODELS ONLY - LATER MODELS HAVE CIRCUITRYINCLUDED ON CONTROL BOARD
THEORY OF OPERATION E-4E-4
LN-25
OPTIONAL CIRCUITS
CONTACTOR
The contactor, contactor PC board, and coldinch switch are commonly incorporated in theLN-25. This feature enables the user to have anelectrically “COLD” gun even though the powersources output terminals are electrically “HOT”.Upon receiving a command from the controlboard, the contactor PC board sends a currentsignal to activate the contactor. The signalcloses the welding current path from the cableto the conductor block, making the gunelectrically “HOT”. The cold inch switch allowsthe user to feed wire without closing thecontactor. In this manner, the electrode wire canbe fed through the gun with the gun tipelectrically “COLD”. See Figure E.4.
GAS SOLENOID Early Models Only (Below 10500)
The gas solenoid feature permits the LN-25 tobe used for gas metal arc welding (GMAW)processes. When the gun trigger circuit isactivated, the control board signals the solenoidPC board to activate the gas solenoid, whichallows shielding gas to flow through the gun tothe arc.
Later Models Only (Above 10500)
The solenoid PC board circuitry has been addedto the Control board and the solenoid PC boardhas been eliminated.
FIGURE E.4 – OPTIONAL CIRCUITS.
NOTE: Unshaded areas of block logic diagrams are the subject of discussion.
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ELECTRODEINPUT CABLE
TO WORKSENSING LEAD
POLARITY
SWITCH
VOLTMETER
CONTROLBOARD
WIRE FEEDMODE SWITCH
SOLENOIDPC BOARD
GASSOLENOID
WIRE SPEEDCONTROL
RANGESWITCH
CONDUCTORBLOCK
MOTOR
HALLEFFECTMODULE
GUNTRIGGER
CONNECTOROPTIONALCONTACTOR
BOARD
COLDINCH
SWITCH
OPTIONALCONTACTOR
GUN CABLE
RPM FEEDBACK
ARMATURE VOLTAGE
EARLY MODELS ONLY - LATER MODELS HAVE CIRCUITRYINCLUDED ON CONTROL BOARD
THEORY OF OPERATION E-5E-5
LN-25
PROTECTIVE DEVICES ANDCIRCUITS
OVERVOLTAGE SHUTDOWN
If the power source open circuit voltage exceedsabout 110-120 volts, the LN-25 will not operate untilthe power source voltage drops below about 102-112volts.
MOTOR OVERLOAD SHUTDOWN
If excessive motor overload occurs (due to prolongedexcessive feeding force, jammed drive rolls or shortedmotor leads) the LN-25 will shut down within a fewseconds after the overload occurs. The shutdown willreset automatically when the gun trigger is released,but will reoccur if the overload situation is not remedied.
CONTROL PC BOARD FUSES
On G1757-2 thru -5 part no. PC boards, the 1/8 ampfuse interrupts the 500A lead to the trigger switch.On G1757-1 PC boards, a 5 amp fuse was used tointerrupt the 667 lead. The LN-25 will not operate ifthe fuse is blown.
On G1757-6 (or higher) part no. PC boards, the 1/8amp fuse was replaced with electronic protection fortrigger circuit faults to electrode circuit.
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NOTES E-6E-6
LN-25
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TABLE OF CONTENTS- TROUBLESHOOTING AND REPAIR SECTION -
• Never work on the inside of the machine without removing theinput power. You can receive a life threatening electrical shock ifyou fail to do this. Only qualified technicians should performinstallation, maintenance, and troubleshooting work on themachine.
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F-2TROUBLESHOOTING AND REPAIRF-2
LN-25
If for any reason you do not understand the test procedures or are unable to perform thetests/repairs safely, contact the Lincoln Electric Service Department for technicaltroubleshooting assistance before you proceed. Call 1-800-833-9353.
Service and Repair should only be performed by Lincoln Electric Factory TrainedPersonnel. Unauthorized repairs performed on this equipment may result in dangerto the technician and machine operator and will invalidate your factory warranty. Foryour safety and to avoid Electrical Shock, please observe all safety notes andprecautions detailed throughout this manual.
This Troubleshooting Guide is provided tohelp you locate and repair possible machinemalfunctions. Simply follow the three stepprocedure below.
Step 1. LOCATE PROBLEM (SYMPTOM).Look under the column labeled “PROBLEM(SYMPTOMS)”. This column describespossible symptoms that the machinery mayexhibit. Find the listing that best describesthe symptom that the machine is exhibiting.Symptoms are grouped according to:feeding problems and function problems.
Step 2. PERFORM EXTERNAL TESTS.The second column labeled “POSSIBLEAREAS OF MISADJUSTMENT(S)” lists theobvious external possibil i t ies that maycontribute to the machine symptom.Perform these tests/checks in the orderl isted. In general, these tests can beconducted without removing the case wrap-around cover.
Step 3. PERFORM COMPONENT TESTS.The last column labeled “RECOMMENDEDCOURSE OF ACTION” lists the most likelycomponents that may have failed in yourmachine. It also specifies the appropriatetest procedure to verify that the subjectcomponent is either bad or good. If thereare a number of possible components,check the components in the order listed toeliminate one possibility at a time until youlocate the cause of your problem.
All the necessary test specifications andrepair procedures are described in detailfollowing the troubleshooting guide. Allelectrical test points, terminal strips,junctions, etc., can be found on theelectrical wiring diagrams and schematicsin the Electrical Diagram Section.
WARNING
CAUTION
How To Use Troubleshooting Guide
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F-3TROUBLESHOOTING AND REPAIRF-3
LN-25
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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 abilitythat the PC board is the most likely componentcausing the 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 staticelectrical damage and electrical shock. Readthe warning inside the static resistant bag andperform the following procedures:
PC board can be damaged by static electricity.
- Remove your body’s staticcharge before opening the static-shielding bag. Wear an anti-staticwrist strap. For safety, use a 1Meg ohm resistive cord connectedto a grounded part of theequipment frame.
- If you don’t have a wrist strap,touch an un-painted, grounded,part of the equipment frame. Keeptouching the frame to preventstatic build-up. Be sure not totouch any electrically live parts atthe same time.
- Tools which come in contact with the PC board mustbe either conductive, anti-static or static-dissipative.
ELECTRIC SHOCKcan kill.
• Have an electrician install andservice this equipment. Turn theinput power OFF at the fuse boxbefore working on equipment. Donot touch electrically hot parts.
- 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-shield-ing bag.
- 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 failuresymptom has been corrected by thereplacement PC board.
NOTE: It is desirable to have a spare (known good)PC board available for PC board troubleshooting.
NOTE: Allow the machine to heat up so that allelectrical components can reach their operatingtemperature.
5. Remove the replacement PC board andsubstitute it with the original PC board torecreate the original problem.
a. If the original problem does not reappear bysubstituting the original board, then the PCboard was not the problem. Continue to lookfor bad connections in the control wiringharness, junction blocks, and terminal strips.
b. If the original problem is recreated by thesubstitution of the original board, then the PCboard was the problem. Reinstall thereplacement PC board and test the machine.
6. Always indicate that this procedure wasfollowed when warranty reports are to besubmitted.
NOTE: Following this procedure and writing on thewarranty report, “INSTALLED AND SWITCHED PCBOARDS TO VERIFY PROBLEM,” will help avoiddenial of legitimate PC board warranty claims.
PC BOARD TROUBLESHOOTING PROCEDURES
ATTENTIONStatic-SensitiveDevicesHandle only atStatic-SafeWorkstations
WARNING
CAUTION
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1. With the gun trigger circuitactivated and the mode switchin the CV position, check forthe presence of 2 to 23 VDC atleads 539 to 541. This is thenormal range for armaturevoltage, which is dependent onthe wire speed setting.
2. If the normal armature voltageis present at leads 539 to 541,then the motor or motorbrushes may be faulty. Checkor replace.
3. If the correct armature voltageis missing, then remove anyoption plugs that may beconnected to J3 on the controlboard. Install the jumper pluginto the J3 receptacle. If theproblem is solved, then theoption board may be faulty.
4. Check the wire speed control,range switch and associatedwiring to the control board.
5. If the correct armature voltageis still not present at leads 539to 541, then the control boardmay be faulty. Replace.
FEEDING PROBLEMS
Observe Safety Guidelinesdetailed in the beginning of this manual.
Troubleshooting Guide – See Wiring Diagrams for location of specifiedcomponents. See Wiring Diagrams for troubleshooting of specific circuits.
NOTE: Many options and possible option combinations are available for the LN-25. In many cases, it is bestto disconnect the options and test the LN-25 in its “basic” form. In this manner, many possible faulty circuitscan be isolated and/or eliminated from the troubleshooting procedure.
F-4TROUBLESHOOTING AND REPAIRF-4
LN-25
PROBLEMS(SYMPTOMS)
POSSIBLE AREAS OFMISADJUSTMENT(S)
RECOMMENDEDCOURSE OF ACTION
When gun trigger is pulled, there isno wire feed.
1. Check to see if the drive rollsare turning when the guntrigger is pulled. If the driverolls are turning, then check fora mechanical restriction in thewire feed path.
2. If the drive rolls do not turn,then check to ensure the powersource is on and an opencircuit voltage (OCV) is presentat the weld terminals.
3. Make sure the LN-25 work clipis connected to the work pieceor work terminal.
4. Ensure the LN-25 polarityswitch matches the electrodepolarity.
5. Check if the jumper plug on thecontrol board or contactorboard (if used) is loose ormissing.
6. Make certain the power sourceopen circuit voltage is above15 VDC but not more than 110VDC.
7. Check if the gun trigger isfaulty. Repair or replace.
8. On “older” control boards,check the 1/8 amp fuse. If“blown”, the gun may be faulty.
Major physical or electricaldamage is evident when the boxcover is removed.
1. Contact Lincoln ElectricService Department 1-800-833-9353 (WELD).
If for any reason you do not understand the test procedures or are unable to perform the tests/repairs safely,contact the Lincoln Electric Service Department for technical troubleshooting assistance before you proceed.Call 1-800-833-9353.
CAUTION
The wire stops or stubs whilewelding.
FEEDING PROBLEMS (Continued)
TROUBLESHOOTING AND REPAIR
Observe Safety Guidelinesdetailed in the beginning of this manual.
Troubleshooting Guide – See Wiring Diagrams for location of specifiedcomponents. See Wiring Diagrams for troubleshooting of specific circuits.
F-5F-5
LN-25
PROBLEMS(SYMPTOMS)
POSSIBLE AREAS OFMISADJUSTMENT(S)
RECOMMENDEDCOURSE OF ACTION
The wire feeds for a short period oftime but then stops feeding. Whenthe gun trigger is released andthen retriggered, the wire resumesfeeding but soon stops again.
1. The drive motor may beoverloaded. Check the wirefeeding path for mechanicalrestrictions.
2. While welding make certain thepower source arc voltage isstaying above 15 VDC. Thefeeder will not function properlyon less than 15 VDC.
1. Check the motor armaturecurrent through either of thearmature leads (539 or 541). Atypical value is 4 amps DC.
2. If 5 amps or less is indicatedand the armature voltage isbeing disabled by the controlboard, then the control boardmay be faulty. Replace.
3. If more than 5 amps isindicated, then the motor isdrawing too much armaturecurrent. Check and or replacethe motor brushes.
4. The motor or gearbox may befaulty. Replace.
1. If the LN-25 is connected to aconstant current power source,the arc voltage may be“dipping” below the 15 VDCthreshold that is essential forproper LN-25 operation.
2. Try connecting the LN-25 to aconstant voltage power sourceor a flatter slope output.
3. Make sure the wire feed modeswitch (S3) is in the correctposition for the power sourcebeing used, and proper speedsetting is used for theprocedure.
4. Check for mechanicalrestrictions in the wire feedpath.
1. Monitor the motor armaturevoltage (leads 539 to 541).Normal range is 2 to 23 VDC.If the armature voltage isproper, then check or replacethe motor brushes.
2. If the motor armature voltage isnot correct, then the controlboard may be faulty. Replace.
If for any reason you do not understand the test procedures or are unable to perform the tests/repairs safely,contact the Lincoln Electric Service Department for technical troubleshooting assistance before you proceed.Call 1-800-833-9353.
CAUTION
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1. Perform the Contactor Test.
2. The contactor PC board maybe faulty. Replace.
FUNCTION PROBLEMS (Continued)
Observe Safety Guidelinesdetailed in the beginning of this manual.
Troubleshooting Guide – See Wiring Diagrams for location of specifiedcomponents. See Wiring Diagrams for troubleshooting of specific circuits.
The gas solenoid valve will notfunction.
1. Make sure the LN-25 isequipped with a gas solenoidvalve and properly connected.
2. Make sure the gas supply isadequate and the gas hosesare not loose or kinked.
1a.Perform the Solenoid PCBoard and Gas SolenoidValve Test (for codes below10500 only).
1b. Perform the Control PCBoard and Gas SolenoidValve Test (for codes above10500 only).
2. If a K434-1 gas flow timer kit isinstalled in the unit, disconnectand plug in the timer jumperplug. If the gas solenoidfunctions, then replace theK434-1 kit.
3. The contactor board or remotecontrol board (if used) may befaulty.
4. The control board may befaulty. Replace.
F-6TROUBLESHOOTING AND REPAIRF-6
LN-25
PROBLEMS(SYMPTOMS)
POSSIBLE AREAS OFMISADJUSTMENT(S)
RECOMMENDEDCOURSE OF ACTION
The wire feed motor runs very fastand there is no control.
1. Make sure the mode switch(S3) is in the CV mode.
2. Make sure the wire speedcontrol and the wire speedrange switch (S2) are setcorrectly.
1. Perform the Wire Drive MotorTest.
2. Perform the Hall EffectModule Test.
3. The control board may befaulty. Replace.
The contactor does not function. 1. Make certain the LN-25 isequipped with a contactor andproperly connected.
2. Check the connections to thecontactor PC board.
If for any reason you do not understand the test procedures or are unable to perform the tests/repairs safely,contact the Lincoln Electric Service Department for technical troubleshooting assistance before you proceed.Call 1-800-833-9353.
CAUTION
NOTES F-7F-7
LN-25
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TROUBLESHOOTING AND REPAIR F-8F-8
LN-25
TEST DESCRIPTION
This test will determine if the gas solenoid valve or the solenoid PC board are functional.
MATERIALS NEEDED
Phillips Head Screwdriver12 VDC SupplyVolt/OhmmeterDC Voltage Source (25 to 100 VDC)
GAS SOLENOID VALVE AND SOLENOID PC BOARD TEST(FOR CODES BELOW 10500 ONLY)
Service and repair should only be performed by Lincoln Electric factory trainedpersonnel. Unauthorized repairs performed on this equipment may result indanger to the technician or machine operator and will invalidate your factorywarranty. For your safety and to avoid electrical shock please observe all safetynotes and precautions detailed throughout this manual.
If for any reason you do not understand the test procedures or are unable toperform the test/repairs safely, contact the Lincoln Electric service departmentfor technical troubleshooting assistance before you proceed. Call 1-800-833-9353(WELD).
WARNING
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TROUBLESHOOTING AND REPAIR F-9F-9
LN-25
TEST PROCEDURE
GAS SOLENOID VALVE
1. Open the case door. Remove the wirereel by removing the retaining collar.See Figure F.1.
2. Remove the screws holding thecontrol box cover in place and removethe control box cover. See Figure F.1.
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(continued)
FIGURE F.1 – CONTROL BOX COVER REMOVAL.
DESIREDIN/MIN
ARCVOLTS
USED
CCWIRE
SPEEDSETTING
(HI of LOWRANGE)
M-15242
PRESETTING
CCMODE
WIRESPEED:
Selecthorisontal
linefor
DESIRED
IN/MIN.
Selectdiagonal
linefor ARC
VOLTS
USED.
Determine
verticalline
wherelines
cross.
Thisvertical
lineis
CCWIRE
SPEED
SETTING,
onfront
dial.
Setswitch
toCC,
andset
proper
ARCVOLTS
whileweldi
(Seeexample
for 375IN/MIN
at29
VOLTS.)
WIRESPEED
CALIBRATED
ININ/MIN
WIRESPEED
CALIBRATED
PERGRAPH
VARIABLE
WIRE
SPEEDFOR
CC
POWERSOURCE
CONSTANT
WIRE
SPEEDFOR
CV
POWERSOURCE
WIRE
FEED
MORE
1.
2.
3.
4.
5.
700
650
600
550
500
450
400
350
300
250
200
150
100
5050
100150
200250
300350
400450
500550
600650
700
35
31
29
27
25
23
21
19
17
15
COLD INCHT13086-99
CASE DOOR
CONTROL BOXCOVER
SCREW
WIRE REEL RETAININGCOLLAR
SCREW
TROUBLESHOOTING AND REPAIR F-10F-10
LN-25
3. Locate and remove the two solenoidleads from the solenoid valve (Forcodes 9812 and below, remove thetwo leads from the solenoid PCboard). See Figure F.2.
4. Make sure the gas supply for thesolenoid is hooked up, and then apply12 VDC to the gas solenoid.
5. If the solenoid activates and allowsgas flow, then the solenoid valve isgood.
NOTE: There should not be any gas flowuntil the solenoid is activated.
6. If the solenoid does not activate andallows gas to flow, then the solenoidis faulty. Replace.
7. The normal solenoid resistance isapproximately 20 to 27 ohms.
GAS SOLENOID VALVE AND SOLENOID PC BOARD TEST(continued)
FIGURE F.2 – SOLENOID LEADS.
SOLENOID LEADSSOLENOID LEADS
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TROUBLESHOOTING AND REPAIR F-11F-11
LN-25
SOLENOID PC BOARD
1. Apply at least 25 VDC but no morethan 100 VDC to the LN-25 from theelectrode cable to the work sensinglead. Make sure the polarity switch isset to match the polarity of theelectrode cable. For example, if theelectrode cable is positive and thework sensing lead is negative, set thepolarity switch to posit ive. SeeFigure F.3.
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(continued)
FIGURE F.3 – APPLIED VOLTAGE POLARITY.
ELECTRODE CABLE
POLARITYSWITCH
WORKSENSING LEAD
TROUBLESHOOTING AND REPAIR F-12F-12
LN-25
2. Check for the presence of the DCvoltage applied from lead 624A(+) tolead 621(-). See Figure F.4
3. Check for the presence of 12 VDCfrom lead 512(+) to lead 621(-).
4. Check for the presence of 10 VDCfrom lead 606(+) to lead 621(-). Whenthe LN-25 trigger circuit is activated,the voltage should drop to about1 VDC.
5. If the above voltage readings aregood and the solenoid valve is
functional, the solenoid PC boardmay be faulty.
6. If the above voltage checks are notcorrect, the control board, contactorboard (if used), remote control board(if used) and/or wiring harness maybe faulty. Refer to the wiring diagramsin the Electrical Diagrams Section.
The appropriate jumper plugs may beused to isolate and check suspectcontactor or remote control boards.
GAS SOLENOID VALVE AND SOLENOID PC BOARD TEST (continued)
FIGURE F.4 – PC BOARD FOR K430-1 GAS SOLENOID KIT.
PC BOARD FOR K430 GAS SOLENOID KIT.
624A
512512
624A 621
J11J11621621
606
624A 512 621
M15202M15202
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NOTES F-13F-13
LN-25
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TROUBLESHOOTING AND REPAIR F-14F-14
LN-25
GAS SOLENOID VALVE AND CONTROL PC BOARD TEST(FOR CODES ABOVE 10500 ONLY)
WARNING
Service and repair should only be performed by Lincoln Electric factory trainedpersonnel. Unauthorized repairs performed on this equipment may result indanger to the technician or machine operator and will invalidate your factorywarranty. For your safety and to avoid electrical shock please observe all safetynotes and precautions detailed throughout this manual.
If for any reason you do not understand the test procedures or are unable toperform the test/repairs safely, contact the Lincoln Electric service departmentfor technical troubleshooting assistance before you proceed. Call 1-800-833-9353(WELD).
TEST DESCRIPTION
This test will determine if the gas solenoid valve or the control PC board valve actuationcircuitry is functional.
MATERIALS NEEDED
Phillips Head Screwdriver12 VDC SupplyVolt/OhmmeterDC Voltage Source (25 to 100 VDC)
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TROUBLESHOOTING AND REPAIR F-15F-15
LN-25
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(FOR CODES ABOVE 10500 ONLY) (continued)
FIGURE F.5 – CONTROL BOX COVER REMOVAL.
DESIREDIN/MIN
ARCVOLTS
USED
CCWIRE
SPEEDSETTING
(HI of LOWRANGE)
M-15242
PRESETTING
CCMODE
WIRESPEED:
Selecthorisontal
linefor
DESIRED
IN/MIN.
Selectdiagonal
linefor ARC
VOLTS
USED.
Determine
verticalline
wherelines
cross.
Thisvertical
lineis
CCWIRE
SPEED
SETTING,
onfront
dial.
Setswitch
toCC,
andset
proper
ARCVOLTS
whileweldi
(Seeexample
for 375IN/MIN
at29
VOLTS.)
WIRESPEED
CALIBRATED
ININ/MIN
WIRESPEED
CALIBRATED
PERGRAPH
VARIABLE
WIRE
SPEEDFOR
CC
POWERSOURCE
CONSTANT
WIRE
SPEEDFOR
CV
POWERSOURCE
WIRE
FEED
MORE
1.
2.
3.
4.
5.
700
650
600
550
500
450
400
350
300
250
200
150
100
5050
100150
200250
300350
400450
500550
600650
700
35
31
29
27
25
23
21
19
17
15
COLD INCHT13086-99
CONTROL BOXCOVER
SCREW
WIRE REEL RETAININGCOLLAR
SCREW
SCREWS
TEST PROCEDURE
GAS SOLENOID VALVE
1. Open the case door. Remove the wirereel by removing the retaining collar.See Figure F.5.
2. Remove the screws holding thecontrol box cover in place and removethe control box cover. See Figure F.5.
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TROUBLESHOOTING AND REPAIR F-16F-16
LN-25
3. Locate and remove the two solenoidleads #690 and #691 from thesolenoid valve. See Figure F.6.
4. Make sure the gas supply for thesolenoid is hooked up, and then apply12 VDC to the gas solenoid.
5. If the solenoid activates and allowsgas flow, then the solenoid valve isgood.
NOTE: There should not be any gas flowuntil the solenoid is activated.
6. If the solenoid does not activate andallows gas to flow, then the solenoidis faulty. Replace.
7. The normal solenoid resistance isapproximately 20 to 27 ohms.
GAS SOLENOID VALVE AND CONTROL PC BOARD TEST(FOR CODES ABOVE 10500 ONLY) (continued)
FIGURE F.6. – SOLENOID LEADS.
SOLENOID LEADS
TROUBLESHOOTING AND REPAIR F-17F-17
LN-25
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(FOR CODES ABOVE 10500 ONLY) (continued)
FIGURE F.7. – APPLIED VOLTAGE POLARITY.
WORK SENSING LEAD
POLARITYSWITCH
ELECTRODECABLE
CONTROL PC BOARD SOLENOIDCIRCUITRY TEST
1. Apply at least 25 VDC but no morethan 100 VDC to the LN-25 from theelectrode cable to the work sensinglead. Make sure the polarity switch isset to match the polarity of theelectrode cable. For example, if theelectrode cable is positive and thework sensing lead is negative, set thepolarity switch to posit ive. SeeFigure F.7.
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TROUBLESHOOTING AND REPAIR F-18F-18
LN-25
690
691
512500
555667621
J1 J3 J4 J2
2. Check for the presence of the DCvoltage applied from plug J1 pin 1(667+) to plug J1 pin 3 621(-). SeeFigure F.8.
3. Check for the presence of 5 to 6 VDCfrom lead 690(+) to lead 691(-) atsolenoid valve. The LN-25 triggercircuit must be activated or the purgebutton must be pressed.
4. If the above voltage reading is notgood at the solenoid valve, check for
5 to 6VDC at plug J2 pin 3 lead690(+) & pin 6 lead 691 (-). SeeFigure F.8.
5. If the above voltage check is notcorrect, the control board may befaulty. Refer to the wiring diagrams inthe Electrical Diagrams Section.
The appropriate jumper plugs may beused to isolate and check suspectcontactor or remote control boards.
GAS SOLENOID VALVE AND CONTROL PC BOARD TEST (FOR CODES ABOVE 10500 ONLY) (continued)
FIGURE F.8. – CONTROL PC BOARD.
NOTES F-19F-19
LN-25
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TROUBLESHOOTING AND REPAIR F-20F-20
LN-25
HALL EFFECT MODULE TEST
TEST DESCRIPTION
This test will determine if the hall effect module is functioning correctly.
MATERIALS NEEDED
Phillips Head ScrewdriverVolt/OhmmeterDC Voltage Source (25 to 100 VDC)
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Service and repair should only be performed by Lincoln Electric factory trainedpersonnel. Unauthorized repairs performed on this equipment may result indanger to the technician or machine operator and will invalidate your factorywarranty. For your safety and to avoid electrical shock please observe all safetynotes and precautions detailed throughout this manual.
If for any reason you do not understand the test procedures or are unable toperform the test/repairs safely, contact the Lincoln Electric service departmentfor technical troubleshooting assistance before you proceed. Call 1-800-833-9353(WELD).
WARNING
TROUBLESHOOTING AND REPAIR F-21F-21
LN-25
TEST PROCEDURE
1. Open the case door. Remove the wirereel by removing the retaining collar.See Figure F.5.
2. Remove the screws holding thecontrol box cover in place and removethe control box cover. See Figure F.5.
3. Locate the three hall effect leads 500,512 and 555 incorporated in plug J4on the control board (for codes 9812and below, the leads connect directlyto the control board). Do not removethe leads from the control board. SeeFigure F.9, or F.10. See Figure F.11for codes above 10500.
HALL EFFECT MODULE TEST (continued)FIGURE F.9 – CONTROL PC BOARD (CODES 10148 THRU 10500).
FIGURE F.10 – CONTROL PC BOARD (CODES 9812 AND BELOW).
J4J3J1 J2
541539
555541539
555
500 512
G2196G2196
539 541
512555500
G1757G1757
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TROUBLESHOOTING AND REPAIR F-22F-22
LN-25
4. Apply at least 25 VDC but no morethan 100 VDC to the LN-25 from theelectrode cable to the work sensinglead. Observe polarity and set polarityswitch.
5. Check for the presence of 12 VDCfrom lead 512(+) to lead 500(-). If the12 VDC is not present or low, thecontrol board may be faulty. SeeFigure F.11.
6. Activate the LN-25 trigger circuit,make sure the drive motor is runningand check for the presence ofapproximately 6.0 VDC from lead555(+) to lead 500(-). The value of
6.0 VDC represents the correctfeedback voltage from the hall effectdevice to the control board.
7. If the above voltage reading is notcorrect, the hall effect device mayneed to be adjusted (see theMaintenance Section) or replaced.See the Drive Motor and GearboxReplacement and Access to HallEffect Module procedure.
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512500
555
J1 J3 J4 J2
FIGURE F.11 CONTROL PC BOARD (CODES ABOVE 10500)
G3425
NOTES F-23F-23
LN-25
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TROUBLESHOOTING AND REPAIR F-24F-24
LN-25
WIRE DRIVE MOTOR TEST
TEST DESCRIPTION
The following procedure will determine if the wire drive motor is functional.
MATERIALS NEEDED
Phillips Head ScrewdriverVoltage Source (variable 2 to 23 VDC)Volt/Ohmmeter
Service and repair should only be performed by Lincoln Electric factory trainedpersonnel. Unauthorized repairs performed on this equipment may result indanger to the technician or machine operator and will invalidate your factorywarranty. For your safety and to avoid electrical shock please observe all safetynotes and precautions detailed throughout this manual.
If for any reason you do not understand the test procedures or are unable toperform the test/repairs safely, contact the Lincoln Electric service departmentfor technical troubleshooting assistance before you proceed. Call 1-800-833-9353(WELD).
WARNING
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TROUBLESHOOTING AND REPAIR F-25F-25
LN-25
TEST PROCEDURE
1. Open the case door. Remove the wirereel by removing the retaining collar.See Figure F.5.
2. Remove the screws holding thecontrol box cover in place and removethe control box cover. See Figure F.5.
3. For codes 10148 and above, separatethe in-line connector (containing thedrive motor leads) located behind themylar insulation. Be sure to identifythe correct in-line connector. There isalso an in-line connector for the halleffect module behind the mylarinsulation. See Figure F.12. For codes9812 and below, remove the twomotor leads 539(white) and541(black) from the control PC board.See Figure F.10.
4. Apply a variable DC voltage to thedrive motor from lead 541(black)(+) tolead 539(white)(-).
5. When the supply voltage is variedfrom 2 to 23 VDC, the drive motorspeed (RPM) should vary accordingly.If the motor does not run or vary inspeed, the motor, gearbox or motorbrushes may be faulty. Check orreplace.
6. Check the resistance between eachof the motor leads [541(black) and539(white)] and the motor case. Theresistance should be very high (atleast 500,000 ohms). If the resistanceis low, the motor is grounded to themotor case and should be replaced.
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DRIVE MOTORLEAD IN-LINECONNECTOR
HALL EFFECT MODULELEAD IN-LINECONNECTOR
TROUBLESHOOTING AND REPAIR F-26F-26
LN-25
CONTACTOR & CONTACTOR PC BOARD TEST
TEST DESCRIPTION
The following test will determine if the contactor is functional.
MATERIALS NEEDED
Phillips Head Screwdriver12 VDC SupplyVolt/Ohmmeter
Service and repair should only be performed by Lincoln Electric factory trainedpersonnel. Unauthorized repairs performed on this equipment may result indanger to the technician or machine operator and will invalidate your factorywarranty. For your safety and to avoid electrical shock please observe all safetynotes and precautions detailed throughout this manual.
If for any reason you do not understand the test procedures or are unable toperform the test/repairs safely, contact the Lincoln Electric service departmentfor technical troubleshooting assistance before you proceed. Call 1-800-833-9353(WELD).
WARNING
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TROUBLESHOOTING AND REPAIR F-27F-27
LN-25
CONTACTOR TEST PROCEDURE
1. Open the case door. Remove the wirereel by removing the retaining collar.See Figure F.5.
2. Remove the screws holding thecontrol box cover in place and removethe control box cover. See Figure F.5.
3. Separate the two in-line connectorslocated behind the reel standassembly. See Figure F.13. For codes9812 and below, remove the twocontactor coil leads from thecontactor PC board. See Figure F.14.
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FIGURE F.13. – CONTACTOR LEAD IN-LINE CONNECTORS.
IN-LINECONNECTORS
TROUBLESHOOTING AND REPAIR F-28F-28
LN-25
4. Apply 12 VDC to the contactor coilleads.
Do not leave the 12 VDC applied to thecontactor coil for a prolonged period oftime (15 seconds maximum). Damage tocontactor may result.
5. If the contactor does not activatewhen the 12 VDC is applied, thecontactor is faulty. Replace.
6. If the contactor activates when the 12VDC is applied, check the resistancebetween the two large terminal studswith the contactor activated. The
resistance should be very low (0 to1 ohm).
7. If the resistance is “high” or “open”between the two large terminal studswhen the contactor is activated, thecontactor is faulty. Replace.
8. If the contactor activates and theresistance between the terminals islow when the 12 VDC is applied, thecontactor is good.
NOTE: When the contactor is not activated,the resistance between the terminals shouldbe very high (infinite). If the resistance isalways low, the contacts are “stuck” and thecontactor is faulty. Replace.
CONTACTOR & CONTACTOR PC BOARD TEST (continued)
FIGURE F.14 – CONTACTOR PC BOARD (CODES 9812 AND BELOW).
J6
J7
CONTACTORCOIL LEADS
S20963S20963
CAUTION
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TROUBLESHOOTING AND REPAIR F-29F-29
LN-25
CONTACTOR PC BOARD TEST
1. Check to be sure plug J9, on contactorboard and plug J3, on the control boardare present and secure. See FiguresF.15 and F.16.
2. If optional gas timer pc board isinstalled, remove plug J6 fromcontactor board and install jumperplug. See Wiring Diagram.
3. Apply at least 25VDC but no morethan 100VDC to the LN-25 from theelectrode cable to the work sensinglead. Observe polarity and set polarityswitch.
4. Check for the applied voltage at plugJ9 pins 1 & 2 lead 667(+) and 621(-).See Figure F.16.
5. With the trigger activated, and anormally operating contactorconnected, the voltage measured atthe contactor leads J9 pins 13 & 14 isapproximately 1.0 VDC. See FigureF.16. See the Wiring Diagram. If the1.0 VDC is not present when thetrigger is activated, the contactor boardmay be faulty.
6. Be sure to reconnect all plugspreviously removed.
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690
691
512500
555667621
J1 J3 J4 J2
FIGURE F.15. CONTROL BOARD
FIGURE F.16. CONTACTOR P.C.BOARD
J6 J7
J9
CONTACTORCOIL LEADS
#667
#621
TROUBLESHOOTING AND REPAIR F-30F-30
LN-25
CONTACTOR PC BOARD REPLACEMENT
TOOLS REQUIRED
Phillips Head Screwdriver
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ELECTRIC SHOCKcan kill.
• Observe all safety precautions detailed throughout this manual.Turn off input power to the wire feeder. Only qualified techniciansshould perform installations, maintenance, and troubleshootingwork on the machine.
WARNING
TROUBLESHOOTING AND REPAIR F-31F-31
LN-25
REPAIR PROCEDURE
1. Observe the static electricityprecautions detailed in PC BoardTroubleshooting Procedures at thebeginning of this section.
2. Open the case door. Remove the wirereel by removing the retaining collar.See Figure F.5.
3. Remove the screws holding thecontrol box cover in place and removethe control box cover. See Figure F.5.
4. For codes 10148 and above, removeplug J9 and plug J7 from thecontactor PC board. See Figure F.17.
CONTACTOR PC BOARD REPLACEMENT (continued)
FIGURE F.17. – CONTACTOR PC BOARD (CODES 10148 AND ABOVE).
J6 J7
J9
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TROUBLESHOOTING AND REPAIR F-32F-32
LN-25
5. For codes 9812 and below, removethe contactor coil leads and plug J7from the contactor PC board. See
Figure F.18. Also for codes 9812 andbelow, remove plug J3 from thecontrol PC board. See Figure F.18.
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FIGURE F.18. – CONTROL PC BOARD PLUG LOCATIONS (CODES 9812 AND BELOW).
J1
J2
J3
J4
G1757G1757
6. Remove the four screws from thefront panel holding the contactor PCboard assembly in place. Carefullyremove the contactor PC boardassembly. See Figure F.19.
7. Place the new contactor PC boardassembly in position behind the frontpanel. Secure the contactor PC boardassembly by installing the four screwsinto the front panel.
8. For codes 10148 and above, installplug J9 and plug J7 onto thecontactor PC board. See Figure F.17.
9. For codes 9812 and below, install thecontactor coil leads and plug J7 ontothe contactor PC board. See FigureF.18. Also for codes 9812 and below,install plug J3 onto the control PCboard. See Figure F18.
10. Install the control box cover andsecure by install ing the screwspreviously removed.
11. Install the wire reel and retainingcollar and close the case door.
TROUBLESHOOTING AND REPAIR F-33F-33
LN-25
CONTACTOR PC BOARD REPLACEMENT (continued)
FIGURE F.19. - CONTACTOR PC BOARD REPLACEMENT.
SCREW
CONTACTOR PCBOARD ASSEMBLY
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TROUBLESHOOTING AND REPAIR F-34F-34
LN-25
CONTROL PC BOARD REPLACEMENT
TOOLS REQUIRED
Phillips Head Screwdriver
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ELECTRIC SHOCKcan kill.
• Observe all safety precautions detailed throughout this manual.Turn off input power to the wire feeder. Only qualified techniciansshould perform installations, maintenance, and troubleshootingwork on the machine.
WARNING
TROUBLESHOOTING AND REPAIR F-35F-35
LN-25
REPAIR PROCEDURE
1. Observe the static electricityprecautions detailed in PC BoardTroubleshooting Procedures at thebeginning of this section.
2. Open the case door. Remove the wirereel by removing the retaining collar.See Figure F.5.
3. Remove the screws holding thecontrol box cover in place and removethe control box cover. See Figure F.5.
4. For codes 10148 and above, removethe four plugs J1, J2, J3 and J4. SeeFigure F.20.
5. For codes 9812 and below, removethe four plugs J1, J2, J3 and J4. Also,tag and remove the five individualleads (three hall effect leads 500, 512and 555 and two drive motor leads539 and 541) connected to the controlPC board. See Figure F.21.
6. On older codes, the control PC boardis larger. If necessary, perform theContactor PC Board ReplacementProcedure to remove the contactorPC board. If installed, the remotecontrol PC board may have to beremoved.
CONTROL PC BOARD REPLACEMENT (continued)
FIGURE F.20. – CONTROL PC BOARD PLUG LOCATIONS (CODES 10148 AND ABOVE).
J4J3J1 J2
G2196G2196
539 541
512555500
G1757G1757
FIGURE F.21. – CONTROL PC BOARD (CODES 9812 AND BELOW).
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TROUBLESHOOTING AND REPAIR F-36F-36
LN-25
J6 J7
J9
CONTACTORCOIL LEADS
#667
#621
J6
J7
CONTACTORCOIL LEADS
S20963S20963
FIGURE F.22. – CONTACTOR PC BOARD PLUG LOCATIONS (CODES 10148 AND ABOVE).
FIGURE F.23. – CONTACTOR PC BOARD PLUG LOCATIONS (CODES 10148 AND BELOW).
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7. Remove the screws holding thecontrol PC board to the inside of thecase. Carefully remove the controlboard. See Figure F.24.
8. Place the new control PC board inposition inside the case. Secure thecontrol PC board by installing thescrews from the outside of the case.
9. For codes 10148 and above, installthe four Molex type plugs J1, J2, J3and J4 onto the control PC board.See Figure F.20.
10. For codes 9812 and below, install thefour Molex type plugs J1, J2, J3 andJ4. Also, connect the five individualleads to the control PC board. Ifnecessary, refer to the wiringdiagrams in the Electrical DiagramsSection. See Figure F.21.
11. Install the control box cover andsecure by install ing the screwspreviously removed.
12. Install the wire reel and retainingcollar and close the case door.
CONTROL PC BOARD REPLACEMENT (continued)
FIGURE F.24. – CONTROL BOARD REPLACEMENT.
TROUBLESHOOTING AND REPAIR F-37F-37
LN-25
SCREW
CONTROLPC BOARD
TROUBLESHOOTING AND REPAIR F-38F-38
LN-25
TOOLS REQUIRED
Phillips Head Screwdriver5/16" Nut Driver11/16" Wrench
ELECTRIC SHOCKcan kill.
• Observe all safety precautions detailed throughout this manual.Turn off input power to the wire feeder. Only qualified techniciansshould perform installations, maintenance, and troubleshootingwork on the machine.
WARNING
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(FOR CODES BELOW 10500)
TROUBLESHOOTING AND REPAIR F-39F-39
LN-25
REPAIR PROCEDURE
1. Open the case door. Remove the wirereel by removing the retaining collar.See Figure F.5.
2. Remove the screws holding thecontrol box cover in place and removethe control box cover. See Figure F.5.
3. Remove the baffle from in front of thecontactor. See Figure F.25.
4. Remove the 5/16" screw holding thecontactor in place.
5. Remove the two 11/16" brass nutsholding voltage sensing lead #67 andthe welding cables to the contactor.
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FIGURE F.25 - CONTACTOR REPLACEMENT.
VOLTAGE SENSINGLEAD 67
WELDING CABLES
CONTACTOR
BAFFLE
5/16" SCREW
REEL STANDASSEMBLY
IN-LINECONNECTORS
11/16" BRASSNUTS
TROUBLESHOOTING AND REPAIR F-40F-40
LN-25
6. Disconnect the contactor coil leads byseparating the two in-line connectorsbehind the reel stand assembly. Forcodes 9812 and below, remove thetwo contactor coil leads from thecontactor PC board. See Figure F.25.
7. Cut or remove any cable t ies orharness tape as necessary.
8. Carefully remove the contactor fromthe LN-25.
9. Install a new contactor in the LN-25.
10. Connect the contactor coil lead in-lineconnectors behind the reel standassembly. See Figure F.25. Forcodes 9812 and below, install thecontactor coil leads onto the contactorPC board. See Figure F.23.
11. Install the welding cables and voltagesensing lead #67 to the contactor andsecure with the two 11/16" brass nuts.See Figure F.25.
NOTE: Be sure brass nuts are tight.11 ft-lb torque is recommended.
12. Install the 5/16" screw to secure thecontactor in place.
13. Install the baffle in front of thecontactor.
14. Install the control box cover andsecure by installing the three screws.See Figure F.5.
15. Install the wire reel and retainingcollar and close the case door. SeeFigure F.5.
CONTACTOR REPLACEMENT (continued)
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NOTES F-41F-41
LN-25
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F-42TROUBLESHOOTING AND REPAIRF-42
LN-25
WARNING
CONTACTOR REPLACEMENT(FOR CODES ABOVE 10500)
TOOLS REQUIRED
Phillips Head Screwdriver5/16" Nut Driver11/16" Wrench3/4” Wrench5/8” Wrench
ELECTRIC SHOCKcan kill.
• Observe all safety precautions detailed throughout this manual.Turn off input power to the wire feeder. Only qualified techniciansshould perform installations, maintenance, and troubleshootingwork on the machine.
F-43TROUBLESHOOTING AND REPAIRF-43
LN-25
CONTACTOR REPLACEMENT (continued)
WORK SENSING LEAD
POLARITYSWITCH
ELECTRODECABLE
VOLTAGE SENSINGLEAD #67
WELDING CABLES
CONTACTOR
IN-LINECONNECTORS
11/16" BRASSNUTS
ELECTRODELEAD
FIGURE F.26.
REPAIR PROCEDURE
1. Open the case door. Remove the wirereel by removing the retaining collar.See Figure F.5.
2. Remove the screws holding the controlbox cover in place and remove thecontrol box cover.
3. Remove the two fiber baffles from thearea in front of the contactor. SeeFigure F.25.
4. With a 3/4” wrench, remove theelectrode lead. See Figure F.26.
5. Using the 11/16” wrench, remove thetwo brass nuts from the contactorterminals. Remove the heavy leads andlead #67 from the terminals. Notelocation of lead #67. See Figure F.26.
6. Remove the 5/16” screw holding thecontactor bracket to the spindle bracket.
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F-44TROUBLESHOOTING AND REPAIRF-44
LN-25
7. Disconnect the contactor coil leads byseparating the two in-line connectorsbehind the reel stand assembly.
8. Cut or remove any cable t ies orharness tape as necessary.
9. Carefully remove the contactorassembly from the LN-25.
10. Install a new contactor in the LN-25.
11. Connect the contactor coil lead in-lineconnectors behind the reel standassembly. See Figure F.26.
12. Place contactor assembly in position.
13. Install the 5/16" screw to secure thecontactor to the spindle assembly.
14. Install the welding cables and voltagesensing lead #67 to the contactor andsecure with the two 11/16" brass nuts.See Figure F.26. Be sure brass nutsare t ight. 11 ft- lb torque isrecommended.
15. Install the baffles in front of thecontactor.
16. Install the control box cover andsecure by install ing the screwspreviously removed.
17. Install the wire reel and retainingcollar and close the case door.
18. Install the two 5/8” screws previouslyremoved from the bottom of themachine.
CONTACTOR REPLACEMENT (continued)
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NOTES F-45F-45
LN-25
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TROUBLESHOOTING AND REPAIR F-46F-46
LN-25
GAS SOLENOID VALVE AND/OR SOLENOID PCBOARD (IF PRESENT) REPLACEMENT
TOOLS REQUIRED
Phillips Head Screwdriver3/4" WrenchPliers
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ELECTRIC SHOCKcan kill.
• Observe all safety precautions detailed throughout this manual.Turn off input power to the wire feeder. Only qualified techniciansshould perform installations, maintenance, and troubleshootingwork on the machine.
WARNING
TROUBLESHOOTING AND REPAIR F-47F-47
LN-25
REPAIR PROCEDURE
1. Open the case door. Remove the wirereel by removing the retaining collar.See Figure F.5.
2. Remove the screws holding thecontrol box cover in place and removethe control box cover. See Figure F.5.
NOTE: If only the gas solenoid valve needsreplacing, it may not be necessary todisconnect all of the wiring. Disconnectwiring only as needed.
3. For codes 10148 thru 10500, removeplug J11 from the solenoid PC board.Also, disconnect the two solenoidleads from the gas solenoid valve,and disconnect the purge switchleads. See Figure F.27.
4a. For codes above 10500 remove leads#690 & #691 from the solenoid valve.See Figure F.28.
4b. Using a 5/16” nut driver remove thetwo screws holding the solenoid &purge button assembly to the case.Remove the assembly.
GAS SOLENOID VALVE AND/OR SOLENOID PC BOARD (IFPRESENT) REPLACEMENT (continued)
FIGURE F.30. GAS SOLENOID ASSEMBLY (FOR CODES ABOVE 10500)
5. For codes 9812 and below, removethe two solenoid leads from thesolenoid PC board and disconnect thepurge switch leads. See Figure F.31.Also, remove plug J2 from the controlboard.
6. Remove the gas hose from the gassolenoid nipple. Remove the brassfitting connected to the gas solenoidvalve from the outside of the case.See Figure F.31.
7. Remove the two screws mounting thegas solenoid and assembly bracket tothe case. Carefully remove theassembly.
8. Remove the two screws mounting thegas solenoid valve to the assemblybracket. Remove the gas solenoidvalve.
9. Remove the two screws mounting thesolenoid PC board to the assemblybracket. Remove the solenoid PCboard.
10. Install the replacement solenoid PCboard onto the assembly bracket andsecure with the two mounting screws.
11. Install the replacement gas solenoidvalve onto the assembly bracket andsecure with the two mounting screws.
12. Install the gas solenoid assemblybracket into the case and secure withthe two mounting screws.
13. Install the gas hose onto the gassolenoid nipple. Install the brassfitting into the solenoid valve from theoutside of the case.
14. For codes 10148 thru 10500, installplug J11 onto the solenoid PC board.Connect the leads to the gas solenoidvalve and purge switch.
TROUBLESHOOTING AND REPAIR F-49F-49
LN-25
GAS SOLENOID VALVE AND/OR SOLENOID PC BOARD (IFPRESENT) REPLACEMENT (continued)
FIGURE F.31. – GAS SOLENOID ASSEMBLY FOR EARLIER CODES.
BRASSFITTING
GAS SOLENOIDASSEMBLYMOUNTING
SCREW
GAS SOLENOIDVALVE MOUNTINGSCREW
SOLENOIDPC BOARD
PC BOARDMOUNTING
SCREW
GAS SOLENOIDASSEMBLY BRACKET
GAS HOSE
GAS SOLENOIDNIPPLE
GAS SOLENOIDVALVE
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TROUBLESHOOTING AND REPAIR F-50F-50
LN-25
GAS SOLENOID VALVE AND/OR SOLENOID PCBOARD (IF PRESENT) REPLACEMENT (continued)
15. For codes 9812 and below, installthe two leads from the gas solenoidvalve onto the solenoid PC boardand connect the purge switch leads.Also, install plug J2 onto the controlboard.
16. Install the control box cover andsecure by install ing the threescrews previously removed.
17. Install the wire reel and retainingcollar and close the case door.
NOTES F-51F-51
LN-25
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TROUBLESHOOTING AND REPAIR F-52F-52
LN-25
DRIVE MOTOR AND GEARBOX REPLACEMENT ANDACCESS TO HALL EFFECT MODULE
TOOLS REQUIRED
Phillips Head Screwdriver3/4" Wrench5/8" Wrench7/16" WrenchSlot Head Screwdriver
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ELECTRIC SHOCKcan kill.
• Observe all safety precautions detailed throughout this manual.Turn off input power to the wire feeder. Only qualified techniciansshould perform installations, maintenance, and troubleshootingwork on the machine.
WARNING
TROUBLESHOOTING AND REPAIR F-53F-53
LN-25
REPAIR PROCEDURE
1. Observe the static electricityprecautions detailed in PC BoardTroubleshooting Procedures at thebeginning of this section.
2. Open the case door. Remove the wirereel by removing the retaining collar.See Figure F.5.
3. Remove the screws holding the
control box cover in place and removethe control box cover. See Figure F.5.
4. For codes 10148 and above, separateboth in-line connectors behind themylar insulation. See Figure F.32. Forcodes 9812 and below, remove thetwo armature leads (539 and 541)and the three hall effect module leads(500, 512 and 555) from the controlboard. See Figure F.33.
DRIVE MOTOR AND GEARBOX REPLACEMENT AND ACCESS TOHALL EFFECT MODULE (continued)
FIGURE F.32. – WIRE DRIVE ASSEMBLY REPLACEMENT.
ELECTRODECABLE
1/2" BOLT
MYLARINSULATION IN-LINE
CONNECTORS
WIRE DRIVEASSEMBLY
WIRE DRIVE ASSEMBLYMOUNTING BOLTS(4 PLACES)
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TROUBLESHOOTING AND REPAIR F-54F-54
LN-25
5. Remove the 1/2" bolt securing theelectrode cable to the gear boxconductor block. Remove the fourbolts mounting the wire driveassembly to the bottom of the case.See Figure F.32.
6. Carefully remove the wire driveassembly. See Figure F.32.
7. Remove the two screws and lockwashers holding the rear end plate tothe gearbox and remove the rear endplate. Remove the three drive motormounting screws, flat washers andlock washers (one is inside thegearbox housing). See Figure F.34.
8. Carefully remove the drive motor fromthe gearbox.
NOTE: To access Hall Effect Modulefor adjustment or replacement seeAdjusting Speed Sensor Module inthe maintenance section of thismanual.
9. Install the replacement drive motoronto the gearbox and secure with thethree screws, flat washers and lockwashers. Install the rear end plate,lock washers and screws.
10. Posit ion the wire drive assemblyinside the case and secure to thebottom of the case with the four bolts.Secure the electrode cable to theconductor block with the 1/2" bolt.See Figure F.32.
11. For codes 10148 and above, connectboth in-line connectors and positionthem behind the mylar insulation. SeeFigure F.32. For codes 9812 andbelow, install the two armature leads(539 and 541) and the three halleffect module leads (500, 512 and555) onto the control board. SeeFigure F.33.
12. Install the control box cover andsecure by install ing the screwspreviously removed.
13. Install the wire reel and retainingcollar and close the case door.
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OC DRIVE MOTOR AND GEARBOX REPLACEMENT AND ACCESS TO
HALL EFFECT MODULE (continued)
539 541
512555500
G1757G1757
FIGURE F.33. – CONTROL BOARD
TROUBLESHOOTING AND REPAIR F-55F-55
LN-25
DRIVE MOTOR AND GEARBOX REPLACEMENT AND ACCESS TOHALL EFFECT MODULE (continued)
FIGURE F.34. – DRIVE MOTOR REPLACEMENT.
DRIVEMOTOR
GEARBOX
REAR END PLATE
LOCKWASHER
END PLATEMOUNTING SCREW
FLAT WASHER
LOCKWASHER
DRIVE MOTORMOUNTING SCREW
HALL EFFECT MODULE
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TROUBLESHOOTING AND REPAIR F-56F-56
LN-25
RETEST AFTER REPAIR
If a failed test indicates that any mechanical part that could affect the machine’s electricalcharacteristics must be replaced or if any electrical components are repaired or replaced,the machine must be retested and meet the following standards.
LEGENDS1 POLARITY SWITCHS2 WIRE SPEED DIAL RANGE SWITCHS3 WIRE FEED MODE SWITCHS4 COLD INCH SWITCH
622A621500A530A530624606622607512
4321
500
*J8
*J13
123456789101112
7576
77
R3ARC VOLTS
TO CONTROL BOARDTO TIMER P.C. BOARD
3433
4 21
10-23-98E
L10925
WIRING DIAGRAM - LN-25
702
622A621500A530A530624606622607512
43
70027011
500
*J8
*J13
123456789
101112
ABCDEF
757677
7576
77R3
ARC VOLTS
TO CONTROL BOARD
REMOTEP.C. BOARD
TOPOLARITYSWITCH
4333421757677
667
621
ABCDEFGHI
667621
REMOTEP.C. BOARD
}} } } } }
N.E.
N.F.
CONTACTOR CAN BE INSTALLED IN UNITS WITH A G1757-3 (OR HIGHERPART NO.) CONTROL PC BOARD.
WHEN A CONTACTOR IS NOT USED, THE ’67’ LEAD TO THE POLARITYSWITCH COMES FROM THE CONDUCTOR BLOCK AND THE INPUT CABLECONNECTS DIRECTLY TO THE CONDUCTOR BLOCK.
N.H. TOGGLE SWITCH USED ON EARLIER UNITS.
N.G. JUMPER PLUG MUST BE INSTALLED UNLESS OPTIONAL TIMER IS USED.
N.A.
N.B.
WHEN A CONTACTOR IS NOT USED THE JUMPER PLUG MUST BEINSTALLED UNLESS OPTIONAL REMOTE KIT IS BEING USED.
CONNECTIONS AS VIEWED FROM BACK OF RHEOSTAT AND SWITCHES.
N.D. ITEM FACTORY INSTALLED ON SOME MODELS AND OPTIONAL EQUIPMENTON SOME MODELS.
NOTESU B R
OPTIONAL PULSE POWER ADAPTOR KIT
OPTIONAL REMOTE OUTPUT CONTROLTO TIMER P.C. BOARD
500
555
512
*J4
*
606500512607530A530
J10
TIMER P.C.BOARD
TO REMOTEOR CONTACTOR
P.C. BOARD123456
GASSOLENOIDVALVE
N.D.
PURGE
608
67
CONTACTOR
CONTACTOR COIL
N.F.
N.D.,N.E.
INPUTCABLE
N.F.
CONNECTOR CAVITY NUMBER*
500A
607622A512530A667624500A530606621622A
750015
916131210148
11165324
*J6
1 2 3 4 5 6N.G.
530530A607512500606
*J6
1 2 3 4 5 6N.G.
530530A607512500606
700701702
500
607622512530A
624500A530606621622A
622A621500A530A530624606622607512
8765
500
*J8
*J12
123456789
101112
ABCDEF
41422
7576
77R3
ARC VOLTS
TO CONTROL BOARD
REMOTEP.C. BOARD
TO TIMER P.C. BOARD
*J6
1 2 3 4 5 6N.G.
530530A607512500606
4321 2
41424
GH
4
757677
OPTIONAL 42 VOLT REMOTE OUTPUT CONTROL
757677
OPTIONAL REMOTE VOLTAGE CONTROL
7576
77
R3ARC VOLTS
ABCDEF
OPTIONAL TIMER KIT
SOLENOID P.C.BOARD PLUG
OPTIONALCONTACTORP.C. BOARD PLUG
PUSHBUTTONS5
N.L.
N.L.
N.L.
N.J. PROVIDES AN ESD PATHWAY FROM EXPOSED METAL SURFACES TO THE WORK.
N.K. PRESENT ON EUROPEAN MODELS ONLY.
N.L. CONNECTS TO THE BUSHING OF THE COMPONENT.
ESD SNUBBER
N.J.,N.K
S5 PURGE PUSHBUTTON
S5
S2S1
S1
691
690
530
500
S4COLD INCHPUSHBUTTON
SWITCH
N.B., N.D.,N.H.
36
690691
621
G-2
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.Ret
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ELECTRICAL DIAGRAMS G-3
WIRING DIAGRAM - CODE 10100 TO 10500
530C
1 23 4
J6
J7
*
*
530
530B50
0
1
2
3
4
5
6
530A512606607530500
HI LO
523522
667500530621607606512
530A
VM
ARCVOLTMETER
+
667 621
632633
63110K
R1
WIRE SPEEDCONTROL RHEOSTATN.B.
CONTACTORP C BOARD
OPTIONALTIMERPLUG
S2
S3
S1
TO WORK CLIP
BLACK
POS
667
621
67
N.B.
NEG
ABCDE
622A
500A
J5TRIGGERCONNECTOR
7
*J3
3214
2134
621
621
500A667
622A
606512
624A
*
*J2
J1
N.D.
3 6 1 4 10 8 11 2 9
509
632
523
522
633
523
524
631
BLA
CK
BLU
ER
ED
524
523
509
VV CV
N.B.
WH
ITE
539
BLA
CK
541
530B500
530
530C530BB
LAC
K
RED
BLU
E
HALLEFFECTSWITCH
GUN CABLE
N.F.
N.G.
N.D.,N.E.N.A.
S4
N.F.
N.B.
WIRE FEEDMODE SWITCH
POLARITYSWITCH
WIRE SPEED DIAL RANGE SWITCH
COLD INCH
SWITCH PUSHBUTTON
,N.H.
624
11193286574
13141210
J9 *
667621
*41 23
1 2
BLA
CK
WH
ITE
J13
159
16131210148
11165324
13
539
14
541
7 12 5
BLA
CK
WH
ITE
OPTIONAL REMOTEKIT PLUG
CONTROLP.C. BOARD
LEGENDS1 POLARITY SWITCHS2 WIRE SPEED DIAL RANGE SWITCHS3 WIRE FEED MODE SWITCHS4 COLD INCH SWITCH
622A621500A530A530624606622607512
4321
500
*J8
*J13
123456789101112
7576
77
R3ARC VOLTS
TO CONTROL BOARDTO TIMER P.C. BOARD
3433
4 21
6-14-96D
L9644
WIRING DIAGRAM - LN-25
702
622A621500A530A530624606622607512
43
70027011
500
*J8
*J13
123456789
101112
ABCDEF
757677
7576
77R3
ARC VOLTS
TO CONTROL BOARD
REMOTEP.C. BOARD
TOPOLARITYSWITCH
4333421757677
667
621
ABCDEFGHI
667621
REMOTEP.C. BOARD
}} } } } }
N.E.
N.F.
CONTACTOR CAN BE INSTALLED IN UNITS WITH A G1757-3 (OR HIGHERPART NO.) CONTROL PC BOARD.
WHEN A CONTACTOR IS NOT USED, THE ’67’ LEAD TO THE POLARITYSWITCH COMES FROM THE CONDUCTOR BLOCK AND THE INPUT CABLECONNECTS DIRECTLY TO THE CONDUCTOR BLOCK.
N.H. TOGGLE SWITCH USED ON EARLIER UNITS.
N.G. JUMPER PLUG MUST BE INSTALLED UNLESS OPTIONAL TIMER IS USED.
N.A.
N.B.
WHEN A CONTACTOR IS NOT USED THE JUMPER PLUG MUST BEINSTALLED UNLESS OPTIONAL REMOTE KIT IS BEING USED.
CONNECTIONS AS VIEWED FROM BACK OF RHEOSTAT AND SWITCHES.
N.D. ITEM FACTORY INSTALLED ON SOME MODELS AND OPTIONAL EQUIPMENTON SOME MODELS.
NOTESU B R
OPTIONAL PULSE POWER ADAPTOR KIT
OPTIONAL REMOTE OUTPUT CONTROLTO TIMER P.C. BOARD
500
555
512
*J4
*
606500512607530A530
J10
TIMER P.C.BOARD
TO REMOTEOR CONTACTOR
P.C. BOARD123456
GASSOLENOIDVALVE
N.D.
PURGE
608
608621
512624A
606
N.D.
621
1
53 7 6 8 42
GAS SOLENOIDP C BOARD *J11
67
CONTACTOR
CONTACTOR COIL
N.F.
N.D.,N.E.
INPUTCABLE
N.F.
CONNECTOR CAVITY NUMBER*
500A
607622A512530A667624500A530606621622A
750015
916131210148
11165324
*J6
1 2 3 4 5 6N.G.
530530A607512500606
*J6
1 2 3 4 5 6N.G.
530530A607512500606
700701702
500
607622512530A
624500A530606621622A
622A621500A530A530624606622607512
8765
500
*J8
*J12
123456789
101112
ABCDEF
41422
7576
77R3
ARC VOLTS
TO CONTROL BOARD
REMOTEP.C. BOARD
TO TIMER P.C. BOARD
*J6
1 2 3 4 5 6N.G.
530530A607512500606
4321 2
41424
GH
4
757677
OPTIONAL 42 VOLT REMOTE OUTPUT CONTROL
757677
OPTIONAL REMOTE VOLTAGE CONTROL
7576
77
R3ARC VOLTS
ABCDEF
OPTIONAL TIMER KIT
SOLENOID P.C.BOARD PLUG
OPTIONALCONTACTORP.C. BOARD PLUG
PUSHBUTTONS5
N.L.
N.B.,N.D.,
N.L.
N.L.
N.J. PROVIDES AN ESD PATHWAY FROM EXPOSED METAL SURFACES TO THE WORK.
N.K. PRESENT ON EUROPEAN MODELS ONLY.
N.L. CONNECTS TO THE BUSHING OF THE COMPONENT.
ESD SNUBBER
N.J.,N.K
S5 PURGE PUSHBUTTON
S5
S2S1
S1
G-3
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.Ret
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ELECTRICAL DIAGRAMS G-4
WIRING DIAGRAM - BELOW CODE 9900
530C
1 23 4
J6
J7
*
*
530
530B50
0
1
2
3
4
5
6
530A512606607530500
HI LO
523522
667500530621607606512
530A
VM
ARCVOLTMETER
+
667 621
N.D.
632633
63110K
R1
WIRE SPEEDCONTROL RHEOSTATN.B.
CONTACTORP C BOARD
OPTIONALTIMERPLUG
S2
S3
S1
TO WORK CLIP
BLACK
POS
667
667
621
621
67
N.B.
NEG
ABCDE
622A
500A
J5TRIGGERCONNECTOR
ARC SOLENOIDP C BOARD
GASSOLENOIDVALVE
N.D.
PURGE
621
608
608621
512624A
606
N.D.500
607622512530A667
624500A530606621622A
500
607622512530A667
624500A530606621622A
1
10
23456
789
1112
*J3
1234
1234
621
621
500A667
622A
606512
624A
*
*J2
J1
SOLENOID P CBOARD PLUG
N.D.
1 2 3 4 5 6 7 8 9
509
632
523
522
633
523
524
631
512
500
555
BLA
CK
BLU
ER
ED
524
523
509
VV CV
N.B.
BLACK
WHITE539
541
WH
ITE
539
BLA
CK
541
530B500
530
530C530B
N.B. ,N.D.
BLA
CK
RED
BLU
EH
ALL
EFFE
CT
MO
DU
LE
67
CONTACTOR
CONTACTOR COIL
N.F.
GU
N C
ABLE
N.F.
N.G.
N.D.,N.E.
CONTACTORP C BOARD PLUG
N.A.
OPTIONAL REMOTEKIT PLUG
*J4
CONTROLP C BOARD
N.D.,N.E.
S4
ELECTRICAL SYMBOLS PER E1537
LEGENDS1 POLARITY SWITCHS2 WIRE SPEED DIAL RANGE SWITCHS3 WIRE FEED MODE SWITCHS4 COLD INCH SWITCH
INPUTCABLE
NOTES
N.A. WHEN A CONTACTOR IS NOT USED THEJUMPER PLUG MUST BE INSTALLED UNLESSOPTIONAL REMOTE KIT IS BEING USED.
N.B. CONNECTIONS AS VIEWED FROM BACK OF RHEOSTAT AND SWITCHES.
N.D. ITEM FACTORY INSTALLED ON SOME MODELS ANDOPTIONAL EQUIPMENT ON SOME MODELS.
N.E. CONTACTOR CAN BE INSTALLED IN UNITS WITH AG1757-3 (OR HIGHER PART NO.) CONTROLP C BOARD.
N.F. WHEN A CONTACTOR IS NOT USED, THE ’67’ LEAD TO THE POLARITY SWITCH COMES FROM THECONDUCTOR BLOCK AND THE INPUT CABLE CONNECTS DIRECTLY TO THE CONDUCTOR BLOCK.
N.G. JUMPER PLUG MUST BE INSTALLED UNLESSOPTIONAL TIMER IS USED.
LEAD TO THE TRIGGER SWITCH. ON THE G1757-1P C BOARD A 5 AMP FUSE WAS USED TO INTERRUPTTHE 667 LEAD.
/
N.F.
N.B.
147
235689
101112
CONNECTOR CAVITY NUMBER
CAVITY NUMBERING SEQUENCE (COMPONENT SIDE OF BOARD)
*1
42
31
42
31
42356
147
235689
J2 J6J1,J7 J4 J3
WIRE FEEDMODE SWITCH
POLARITYSWITCH
WIRE SPEED DIAL RANGE SWITCH
COLD INCH
SWITCH PUSHBUTTON
,N.H.
TOGGLE SWITCH USED ON EARLIER UNITS.
N.H.
624
FRANCE CANADA AUSTRALIA CAD
9-13-91B
7545 L
2-8011-87
N.C.
N.C. FUSE USED ON EARLIER MODELS ONLY:ON G1757-2 THRU G1757-5 CONTROL P C BOARDS,
A 1 8 AMP FUSE INTERRUPTS THE 500A.
3-91
G-4
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.Ret
urn
to S
ectio
n T
OC
Ret
urn
to S
ectio
n T
OC
Ret
urn
to S
ectio
n T
OC
Ret
urn
to S
ectio
n T
OC
Ret
urn
to M
aste
r T
OC
Ret
urn
to M
aste
r T
OC
Ret
urn
to M
aste
r T
OC
Ret
urn
to M
aste
r T
OC
Ret
urn
to S
ectio
n T
OC
Ret
urn
to S
ectio
n T
OC
Ret
urn
to S
ectio
n T
OC
Ret
urn
to S
ectio
n T
OC
Ret
urn
to M
aste
r T
OC
Ret
urn
to M
aste
r T
OC
Ret
urn
to M
aste
r T
OC
Ret
urn
to M
aste
r T
OC
ELECTRICAL DIAGRAMS G-5
SCHEMATIC - COMPLETE MACHINE - BELOW CODE 9900 ONLY
Ch’ge. Sht. No.
1833
1-25-91N
9-13-91B
1-31-92E
LN-25 OPERATING SCHEMATIC
DAD/JLV
NONE
1833 9-4-87 THP 5-22-92
THE LINCOLN ELECTRIC CO.CLEVELAND, OHIO U.S.A.
EQUIP.TYPE
SCALE
DR DATE CHK REF.
SUBJECT
SUP’S’D’GSHT.NO. G
G
RANGE SWITCHHI - LO
632
522523
N.B.
633 631MAX.
10K OHMSR1
WIRE SPEEDCONTROL RHEOSTAT
N.B.
VOLTMETER
VMB + W
N.F.
667 621
523N.B.
WIRE FEEDMODE SWITCH
VV - CV
WIRE SPEED DIAL
524 509
S3
621TO WORKCLIP
BLACK
S1POLARITYSWITCH
POS
67N.B.
NEG
667
667
621
622A
500A
624A
621
512
606
SOLENOIDKIT PLUG
A
B
C
D
E
622A
500A
J5
TRIGGER
CONNECTOR
PURGEN.F.
621
ARC SOLENOID P.C. BD.
SEE SOLENOID KITSCHEMATIC
GAS SOLENOID VALVEN.F.
509
524
522
633
523
632
631
523
606
530
530A
622A
500A
622
500
512
667
624
621
607
CONTACTORP.C. BD. PLUG
606
530
530A
622A
500A
622
500
512
667
624
621
607
N.A.
OPTIONALREMOTE PLUG
N.F., N.G.606
530
530A
500
512
667
621
607
624
3124
SEE CONTACTORKIT SCHEMATIC
J7 *
1
2
3
4
5
6
CONTACTORP.C. BD.
J6 *
530C530B
500500
530C530B
N.B., N.F., N.L.COLD INCHPUSH BUTTON SWITCH
606
500
512
607
530A
530
N.J.
OPTIONALTIMER PLUG
67
GUN CABLE
N.H.
RU
B
HALLEFFECTMODULE
W539
B541
N.F.
CONTACTOR COIL
CONTACTOR
N.H.
INPUT CABLE
X1, X2 TL431IP PRECISION REFERENCEX3 MC14584B HEX SCHMITT TRIGGERX4 LM2907 FREQUENCY TO VOLTAGE CONVERTERX5, X6 LM324 QUAD OP-AMPX7 THRU X9 LM2901 QUAD COMPARATORX10 MC14013B D-TYPE FLIP-FLOP
OCI 4N35 OPTO-COUPLERX11 MC14066B QUAD ANALOG SWITCH
COLOR LEGEND
B = BLACKU = BLUEH = BROWNR = REDG = GREENW = WHITE
NOTES:
N.A. WHEN A CONTACTOR IS NOT USED, A JUMPER PLUG MUST BE INSTALLED UNLESS OPTIONAL REMOTE OUTPUT KIT IS BEING USED.
N.B. CONNECTIONS AS VIEWED FROM BACK OF RHEOSTAT AND SWITCHES.
CHANGE WITHOUT AFFECTING THE INTERCHANGEABILITY OF A COMPLETE BOARD,N.C. SINCE COMPONENTS OR CIRCUITRY ON A PRINTED CIRCUIT BOARD MAY
THIS DIAGRAM MAY NOT SHOW THE EXACT COMPONENTS OR CIRCUITRY OFCONTROLS HAVING A COMMON CODE NUMBER.
N.D. ON G1757-2 THRU G1757-5 P.C. BOARDS, A 1 8 AMP FUSE INTERRUPTS THE/500A. LEAD. ON THE G1757-1 P.C. BOARD A 5 AMP SLOW BLOW FUSE WAS USEDTO INTERRUPT THE 667 LEAD. R72 WAS 1.5K AND THERE WAS NO R86.
N.E. ACTUAL CIRCUIT OF X3.
C
D
E
F12
10
8
6
YX
5
9
11
13
N.F. ITEM FACTORY INSTALLED ON SOME MODELS AND OPTIONAL EQUIPMENTON OTHER MODELS.
N.G. CONTACTOR CAN BE USED WITH A G1757-3 (OR HIGHER PART NO.) CONTROLP.C. BOARD.
N.H. WHEN A CONTACTOR IS NOT USED THE "67" LEAD TO THE POLARITY SWITCHCOMES FROM THE CONDUCTOR BLOCK AND THE INPUT CABLE CONNECTSDIRECTLY TO THE CONDUCTOR BLOCK.
N.J. JUMPER PLUG MUST BE INSTALLED UNLESS OPTIONAL TIMER IS USED.
N.K. R25 WAS 1K ON G1757-3C (OR LOWER PART NO.) P.C. BOARDS.
WITHOUT AFFECTING THE INTERCHANGEABILITY OF A COMPLETE BOARD, THIS DIAGRAM MAYNOT SHOW THE EXACT COMPONENTS OR CIRCUITRY OF CONTROLS HAVING A COMMON CODE
N.A. SINCE COMPONENTS OR CIRCUITRY ON A PRINTED CIRCUIT BOARD MAY CHANGE
606
512
621
624
622A
606
530
OPTIONAL
500
530
530A
PCB PLUG
622
607607
500
C33 C40
22.1KR79
1.00K
R81
SHOOT-THRU PROTECTION
D29
1.00K
R100
J49
J31
C42
LM2901
X9
3
12
4066B
X11
14
7
22.1K
R80
667
500p
1.00K
R97
J41
1N4005D1
5W3300R
2
D32
16.5KR51
44.2KR50
J410
J42
4.75K
R94
J43
4.75KR84
J411
J46
J48
J44
600V.05C1
1W16VDZ4
1N4005D4 D2
400V300mA
Q2
100
R5
621
40V600mAQ3
621
667
470350V
C2
150V45J
TP1
1N4005D27
10.0
R4
5W10R1
400V
5A
Q1
C318.2K
R6
2.67K
R8
4.75K R12
500
CW
R11
1.3K
R91
C6
+
REF
-TL431
X1
1
6
8
330050V
C5+
REF
-TL431
X2
1
6
84.75K
R7
100
R3
1.820V
C7
500p
5025V
C4
470350V
C9
44.2K
R53
D5
D3
40V600mAQ4
+12VDC5W4700
R13
X61
2
3
4.75KR85
X614
12
13
13.7K
R52
470350V
C8
D14
1.00K
R9
13.7K
R10
1W16VDZ3
FET DRIVER
EQUIP.
J413
15A600V
D30
16A35V
D31
20A500V
Q9
J414
47.5K
R46
CAPACITORS =
600V3AD12
.022/50V
SCHEMATICSUBJECT
TYPE
20A500V
Q8
5W68
R38
.17WR
47
400V.1C26
512
541(B)
539(W)
6.81K
R44
5W4700
R14
2050V
C10
D7
C47
40V600mAQ14
1W12VDZ1
2.43K
R88
200mA7.5-9.0 V
Q15
22.1K
R90
X814
9
8
DC
22.1K
R29
40V600mAQ10
D11
5.62K
R28
5025VC23D10
18.2K
R31
600mA40V
Q11
X91
6
7
7.68K
R87
4584B
X3
14
7
X31213
22.1K
R89
400V.001C44
22.1K
R15
4N35OCI1
4
5
6
400V.0022C11
100V100pC46
X321
100K
R16
C12
X343
X31011
512
512
495
OSCILLATOR4 KHZ
-9V
3.32K
R32
1025V
C22
4.735V
C45
X389
DYNAMIC BRAKING
TO
2194
30A600V
D6
G
+9.50VDC
SUPPLY
MOTOR
NEGATIVE
500p
509
621
512
V.V.SCALER
522
523
632
633
REMOTE PLUGJUMPER
530A
PCB PLUGCONTACTOR
OPTIONAL
WIRE SPEED
WIRE FEED
DIAL RANGE
CONTROL
WIRESPEED
MODE SWITCH
SWITCH
523
524
509
621
500A
667
POLARITYSWITCH
606
PCB 512
TO ARCSOLENOID
CONNECTOR 622ATRIGGER
621
624A
621
667
624
621621
621621
512
621495
C-
FRAME CONNECTION
7-8-94A
11-8-96G
G-7
NOTE: This diagram is for reference only. It may not be accurate for all machines covered by this manual.Ret
urn
to S
ectio
n T
OC
Ret
urn
to S
ectio
n T
OC
Ret
urn
to S
ectio
n T
OC
Ret
urn
to S
ectio
n T
OC
Ret
urn
to M
aste
r T
OC
Ret
urn
to M
aste
r T
OC
Ret
urn
to M
aste
r T
OC
Ret
urn
to M
aste
r T
OC
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 pro-vided for 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 themachine.
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 pro-vided for 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 themachine.
ELECTRICAL DIAGRAMS G-9
PC BOARD ASSEMBLY - CONTROL - CODE 10100 TO 10500
Ch’ge. Sht. No.
2-20-98C
THE LINCOLN ELECTRIC CO.CLEVELAND, OHIO U.S.A.
EQUIP.TYPE
SCALE
DR DATE CHK REF.
SUBJECT
SUP’S’D’GSHT.NO. G
G
ITEM REQ’D PART NO. DESCRIPTION
2196-1 2196-1
CONTROL P.C. BOARD
G1757-6
LN-25
FULL
LJB
4.15
4.73
.38
5.63
2.03
.25
~.040
0
6.00 ~.04
CAPACITORS = MFD/VOLTSRESISTORS = OHMS
XX
XX
X
XX
X
X
XX
XX
XX
XXX
XXXXX
XX
XX
3.00
8.75
9.005.00
10-22-96
CONTROL G2196-1
R88 R87
R94 R95
R3
R6
R7
R
8
R5
R
4
R9
R
91
R12
R10
R17
R16 R15 R89
R90
R73
R81
R83
R60
R63
R76
R61
R64
R69
R74
R77
R62
R66
R67
R68
R79
R80
R82
R59
R70
R75
R78
R65
R71
R18 R19
R24
R26 R27
R54
R52
R51
R20 R21
R57 R56
R55
R25
R50
R53
R84
R85
R58
R23
R37
R45
R33
R
31
R29
R30
R34
R39
R40
R49
R42
R35
R32
R43
R41
R46
R28
R36
R44
C44
C21 C24
Q1
D31
C49
C48
C46
C13
C3
C6
C12
C47
C33
C38
C39
C15
C20
C28
C34
C35
C36
C37
C40
C41
C42
C43
C9
C8
C2
C7
C31
C45
C27
C14
C18
C19
C25
C32
C29
C16
C10
C11
C4
C23
C5
C17
C1
C26
DZ4
DZ2
DZ1
DZ3
D32
D2
D3
D5
D7
D13
D17
D18
D19
D20
D21
D22
D23
D24 D25
D28
D29
D8
D14
D16
D9
D10
D11
D1
D4
D27
X6
X3
X7
X4 X5
X11
X10
X9
X8
X1
X2
TP1
J4 J3 J1 J2
OC
I1
R11
R22
R86
R72
R2
R13
R14
R38
R47
Q15
Q14
Q13
Q12
Q11
Q10
Q7
Q6
Q5
Q4
Q3
Q
2
C22
+
R96
R97
R98 R99
R10
0
C30
R1
D30
D6
Q8
Q9
D12
8-12-94C
11-8-96G
7-8-94A
XXXX
X
X X XX
G-9R
etur
n to
Sec
tion
TO
CR
etur
n to
Sec
tion
TO
CR
etur
n to
Sec
tion
TO
CR
etur
n to
Sec
tion
TO
C
Ret
urn
to M
aste
r T
OC
Ret
urn
to M
aste
r T
OC
Ret
urn
to M
aste
r T
OC
Ret
urn
to M
aste
r T
OC
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 pro-vided for 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 themachine.
ELECTRICAL DIAGRAMS G-10
PC BOARD ASSEMBLY - CONTROL - BELOW CODE 9900
3-17-95B 2-21-97E
THE LINCOLN ELECTRIC CO.CLEVELAND, OHIO U.S.A.
EQUIP.TYPE
SCALE
DR DATE CHK REF.
SUBJECT
SUP’S’D’GSHT.NO. G
G
ITEM REQ’D PART NO. DESCRIPTION
1757-6 1757-6
CONTROL P.C. BOARD
8-23-91
LN-25
FULL
FM 1-21-94
9-13-91B
1-31-92E
1.90 4.20
5.05
6.25 11.00
.25
1.10
10.75
3.20
5.60
2.05
.25
~.040
0
2.275
6.00~.04
X X X XX
XXX
X
XXXX XXX
X
XX
XX
X
XX
X
X
XXXXX
XXX
XX
CAPACITORS = MFD/VOLTSRESISTORS = OHMS
3-4-94
X X X XX
XXX
X
XXXX XXX
X
XX
XX
X
XX
X
X
XXXXX
XXX
XX
LN-25 CONTROLG1757-6
G-10R
etur
n to
Sec
tion
TO
CR
etur
n to
Sec
tion
TO
CR
etur
n to
Sec
tion
TO
CR
etur
n to
Sec
tion
TO
C
Ret
urn
to M
aste
r T
OC
Ret
urn
to M
aste
r T
OC
Ret
urn
to M
aste
r T
OC
Ret
urn
to M
aste
r T
OC
Ret
urn
to S
ectio
n T
OC
Ret
urn
to S
ectio
n T
OC
Ret
urn
to S
ectio
n T
OC
Ret
urn
to S
ectio
n T
OC
Ret
urn
to M
aste
r T
OC
Ret
urn
to M
aste
r T
OC
Ret
urn
to M
aste
r T
OC
Ret
urn
to M
aste
r T
OC
ELECTRICAL DIAGRAMS G-11
SCHEMATIC - CONTACTOR PC BD - ABOVE CODE 10500
POWER SUPPLY SOURCE POINT
CONTACTOR
SUP’S’D’G.
DIODES =
CAPACITORS =
GENERAL INFORMATION LAST NO. USED
LABELS
PULL-IN TIMER
CURRENT LIMIT
11RESISTORS = Ohms (MFD
1A, 400V
( C-
R-
VOLTAGE NET
14
37
D-UNLESS OTHERWISE SPECIFIED)
(UNLESS OTHERWISE SPECIFIED)
.022/50V
SUPPLY
1/4W
COMMON CONNECTION
ELECTRICAL SYMBOLS PER E1537
FRAME CONNECTION
UNLESS OTHERWISE SPECIFIED)
SCALE
EQUIP.
CHK.
LN-25
NONECLEVELAND, OHIO U.S.A.
EARTH GROUND CONNECTION
SCHEMATICCONTACTOR
9/28/90
SUBJECT
TYPE
SHT.
100
R29
512A
MC14538B
X4
16
8
1.820V
C11
LM2901
X5
3
12
621
BACK-UP COIL SUPPLYA
512
NOT SHOW THE EXACT COMPONENTS OR CIRCUITRY OF CONTROLS HAVING A COMMON CODE
400V5AQ1
X51
6
7
D11
D8
33.2R2
NUMBER.
Ch’ge.Sht.No.
WITHOUT AFFECTING THE INTERCHANGEABILITY OF A COMPLETE BOARD, THIS DIAGRAM MAYN.A. SINCE COMPONENTS OR CIRCUITRY ON A PRINTED CIRCUIT BOARD MAY CHANGE
NOTES :
COLD INCH LOCK OUT
CONTACTOR ON
50V2700pfC8
22.1KR36
M19065
E
J66
J7
1
7W2.7
R30600V3A
D1
SWITCH
THE LINCOLN ELECTRIC CO.
DATEDR. MCW NO.
FILE: M19065_1BA
606
512
607
607
606
530A
500
530
621
512
530A
TIMER BOARD
TO
50V.0047C2
100K
R14
RST
/Q
T2QA
B
T1
X4
1
3
4
2
6
5 7
100
R11
1.01W R1
9
X314
8
9
X313
10
11
50V820pC4
511
R15
X31
7
6
X514
8
9
22.1K
R13
1.035V
C3
5.62
K
R17
RST
/Q
T2QA
B
T1
X4
15
13
12
14
10
11 9
J914
22.1K
R9
1A1N4007
1000V
D2
J913
22.1K
R6
1A1000V
D3
1W16VDZ1
5.62K
R10
10K
R16
7.8A800V
Q5
Q32N4401
2.67K
R18
Q42N4403
X32
4
5
512A
621
621
621
512A
621
512A
B
C
22.1K
R7
3.32K
R12
3.32KR37
50V2700pC14
J63
5W3300
R1
+REF
-TL431
X1Q72N4403
560035V
C1
400V300mA
Q2
15.0K
R4
Q62N4401
621
621 621512A
5W2.7
R31
+
REF
-
TL431X2
5W2.7
R32
C9
2.21K
R23
50V0.1
C10
J911 2.8KR
22150K
R20
2.8K
R21
X52
4
5
15.0K
R24
22.1K
R28
22.1K
R25
22.1K
R26
J96
J99
J910
J93
J97
5.62K
R27
J98
J95
J912
X513
10
11
1.82K
R5
100
R3
1W16VDZ2
20A500V
Q8
M19065
LM2901
X3
3
12
C7
D5
C6
D9
621
J7
2
330050V
C5
J65
D10
J61
D
D6
J62
500
530
530
500
J64
COLD INCH
J91
624
667
J94
CONTROL BOARD
J92
2-20-98A
10-23-98E
G-11
NOTE: This diagram is for reference only. It may not be accurate for all machines covered by this manual.
ELECTRICAL DIAGRAMS G-12
SCHEMATIC - CONTACTOR PC BD - CODE 10100 TO 10500
CONTACTOR
EARTH GROUND CONNECTION
SCHEMATIC
NO.SHT.
MCW DATE
SCALECLEVELAND, OHIO U.S.A.
NONEDR.
NOT SHOW THE EXACT COMPONENTS OR CIRCUITRY OF CONTROLS HAVING A COMMON CODE
LN-25THE LINCOLN ELECTRIC CO.
CHK.
WITHOUT AFFECTING THE INTERCHANGEABILITY OF A COMPLETE BOARD, THIS DIAGRAM MAY
FILE: M17621_1AA
50V2700pfC8
9/28/90
EQUIP.
X51
6
7
M17621
SUBJECT
TYPE
621
Ch’ge.Sht.No.
50V2700pfC13
N.A. SINCE COMPONENTS OR CIRCUITRY ON A PRINTED CIRCUIT BOARD MAY CHANGE
NOTES :
621
NUMBER.
621
.022/50V
(UNLESS OTHERWISE SPECIFIED)
UNLESS OTHERWISE SPECIFIED)1/4W
GENERAL INFORMATION
UNLESS OTHERWISE SPECIFIED) 8
POWER SUPPLY SOURCE POINT
LABELS
COMMON CONNECTION
C-
R-
LAST NO. USED
FRAME CONNECTION
VOLTAGE NET
35
D-
13
SUPPLY
ELECTRICAL SYMBOLS PER E1537
1A, 400VRESISTORS = Ohms (
MFDCAPACITORS =
DIODES =
(
B
1.035V
C3
X32
4
5
X514
8
9
512
512A
TIMER BOARD
1.820V
C11C6
J73
J63
2.8K
R21J9
8
600V3A
D1
2.8KR22
LM2901
X5
3
12
D6
J71
330050V
C5
J92
J95
J97
J64
J96
J65
J911
C7
J910
J61
J74
LM2901
X3
3
12
J72
J62
J66
J99
2.21K
R23
J93
J912
C9
J94
621
J91
15.0K
R24
D5
50V0.1
C10
CONTROL BOARD
X513
10
11
7W2.7
R30
D
SWITCHCOLD INCH
624
M17621
500
530
500
667
621
530B
607
530
606
530A
530C
607
512
606
530
500
512
530A
MC14538B
X4
16
8
150K
R20
512A
Q42N4403
5.62K
R10
22.1K
R7
22.1K
R6
621
8A500V
Q5
100
R11
Q32N4401
1W16VDZ1
400V.0047
C2
22.1K
R9
X31
7
6
J914
20A500V
Q8
1W16VDZ2
1A1000V
D3
100
R3
Q72N4403
400V300mA
Q2
5.62K
R27
+
REF
-
TL431X2
5W2.7
R32
+REF
-TL431
X1 560035V
C1
15.0K
R4
1.82K
R5
22.1K
R26
22.1K
R28
RST
/Q
T2QA
B
T1
X4
15
13
12
14
10
11 9
5W2.7
R31
X52
4
5
22.1K
R25
621
621
E
100
R29
J91333.2
R2
1N4005D2
400V5AQ1
1A600v
CONTACTORTO
A
BACK-UP COIL SUPPLY
Q62N4401
512A
5W3300
R1
X313
10
11
X314
8
9
5.62K
R17100K
R14
3.32K
R12D8
D4 3.32K
R35
621
512A
621
PULL-IN TIMER
C
CURRENT LIMIT
1.01W R1
9
511
R15
10K
R16
400V.001C4
2.21K
R18
22.1K
R13
RST
/Q
T2QA
B
T1
X4
1
3
4
2
6
5 7
22.1K
R34
REF.J.J.
7-8-94A
M15428
G-12
NOTE: This diagram is for reference only. It may not be accurate for all machines covered by this manual.Ret
WITHOUT AFFECTING THE INTERCHANGEABILITY OF A COMPLETE BOARD, THIS DIAGRAM MAYNOT SHOW THE EXACT COMPONENTS OR CIRCUITRY OF CONTROLS HAVING A COMMON CODE
NOT SHOW THE EXACT COMPONENTS OR CIRCUITRY OF CONTROLS HAVING A COMMON CODE
22.1
K
R34
D6
SWITCH
500
Ch’ge.Sht.No.
NUMBER.
530C
530
530B
COLD INCH
T2 /QAT1
Q/CD
BX4
10
12
14
13
9
15
11
530
50V2700pfC13
COMMON CONNECTION
50V2700pfC8
22.1
K
R13
1.01WR1
9
N.A. SINCE COMPONENTS OR CIRCUITRY ON A PRINTED CIRCUIT BOARD MAY CHANGEWITHOUT AFFECTING THE INTERCHANGEABILITY OF A COMPLETE BOARD, THIS DIAGRAM MAY
POWER SUPPLY SOURCE POINTNOTES :
DIODES =
CAPACITORS = MFDRESISTORS = Ohms (
1A, 400V
ELECTRICAL SYMBOLS PER E1537
GENERAL INFORMATION
PULL-IN TIMER
SUBJECT
DR.
UNLESS OTHERWISE SPECIFIED)
NONECLEVELAND, OHIO U.S.A.
SCALE
DATEMCW
UNLESS OTHERWISE SPECIFIED).022/50V
(UNLESS OTHERWISE SPECIFIED)
TYPEEQUIP.
M17139
CURRENT LIMIT
SUPPLY
13
J71
D-
35
VOLTAGE NET
FRAME CONNECTION
LAST NO. USED
R-
C-
J61
CONTACTOR
EARTH GROUND CONNECTION
SUP’S’D’G.
P3
LABELS
SCHEMATIC
J72
LN-25
SHT.NO.
8
MC14538B
X4
16
8
X51
6
7
D5
LM2901
X3
3
12
C7
LM2901
X5
3
12
330050V
C51.8
20V
C11C6
X514
8
9
100K
R14
3.32K
R35 X314
8
9
3.32K
R12
1.035V
C3
D4
511
R15
5.62
K
R17
400V.001C4
D8
J73
J74
FILE: M17139-2BB
1W16VDZ1
J64
J63
1A1000V
D3
8A500V
Q5
3
1
2
Q32N4401
B1
Q42N44035600
35V
C1100
R11X31
7
6
5.62K
R10
400V.0047
C2
22.1K
R6
22.1K
R9
2.21K
R18
X32
4
5
22.1K
R7
/CD
Q
A/QB
T2
T1
X4
1
3
5
4
7
2 6
621
512A
621
512A
M17139
TOCONTACTOR
2.21K
R23
2.8K
R21
50V0.1
C10
22.1K
R26
B2
530A
TIMER BOARD
607
606
Q72N4403
512
607
7W2.7
R30
J65
J66 10K
R16
600V3A
D11N4005D2
1
2
1.82K
R5
1W16VDZ2
621621
22.1K
R28
J62
+
REF
-TL431
X1
1
6
8
X313
10
11500
621
621
512A
621
512A
621621
5-21-93E
3-25-94H
G-14
NOTE: This diagram is for reference only. It may not be accurate for all machines covered by this manual.Ret
urn
to S
ectio
n T
OC
Ret
urn
to S
ectio
n T
OC
Ret
urn
to S
ectio
n T
OC
Ret
urn
to S
ectio
n T
OC
Ret
urn
to M
aste
r T
OC
Ret
urn
to M
aste
r T
OC
Ret
urn
to M
aste
r T
OC
Ret
urn
to M
aste
r T
OC
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 pro-vided for 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 themachine.
ELECTRICAL DIAGRAMS G-15
PC BOARD ASSEMBLY-CONTACTOR - ABOVE CODE 10500
CAPACITORS = MFD/VOLTS
ITEM REQ’D PART NO. IDENTIFICATION
INDUCTANCE = HENRYS
10863-1 Ch
’ge.
Sht
. No.
2-2
0-98
A
10-
23-9
8E
7-
2-99
C
LJB
F
ULL
1
-6-9
8
L967
0-1
THE
LINC
OLN
ELEC
TRIC
CO.
CLE
VELA
ND
, OH
IO U
.S.A
.
EQ
UIP
.TY
PE
SC
ALE
SU
BJE
CT
DR
DA
TEC
HK
RE
F.S
UP
’S’D
’GS
HT.
NO
.L
L
1086
3-1
CO
NTA
CTO
R P
.C. B
OA
RD
AS
SEM
BLY
LN-2
5
.25
03.25
3.50 ~.04
0
.55
3.80
5.00~.04
LN-25
CO
NTAC
TOR
R27
R17
R10
R15
R22
R21
R28
R26
R25
R13
R12
R9
R7
R6
R23
R5
R20
R24
R4
R14 R
16
R11
R3
R2
D3
C10
C8
C9
C7
C6
C11
C3 C
5
C1
DZ2
DZ1
D8
D6
D5
X5
X3
J9
J6
R19
R1
R30
Q1 R29
X4
X1
X2
L10863-1
C4
J7
R18
C2
D2
D9
D10
D11
R36
R37
C14
D1
R32
R31
Q6
Q7
Q2 Q3
Q4
Q5
Q8
G-15R
etur
n to
Sec
tion
TO
CR
etur
n to
Sec
tion
TO
CR
etur
n to
Sec
tion
TO
CR
etur
n to
Sec
tion
TO
C
Ret
urn
to M
aste
r T
OC
Ret
urn
to M
aste
r T
OC
Ret
urn
to M
aste
r T
OC
Ret
urn
to M
aste
r T
OC
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 pro-vided for 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 themachine.
ELECTRICAL DIAGRAMS G-16
PC BOARD ASSEMBLY-CONTACTOR - CODE 10100 TO 10500
CAPACITORS = MFD/VOLTS
ITEM REQ’D PART NO. IDENTIFICATION
INDUCTANCE = HENRYS
9670-1 Ch
’ge.
Sht
. No.
7-
8-94
A
8-1
2-94
C
2-2
0-98
C
R.T
.
F
ULL
L9
185-
2
4
-28-
94
THE
LINC
OLN
ELEC
TRIC
CO.
CLE
VELA
ND
, OH
IO U
.S.A
.
EQ
UIP
.TY
PE
SC
ALE
SU
BJE
CT
DR
DA
TEC
HK
RE
F.S
UP
’S’D
’GS
HT.
NO
.L
L96
70-1
CO
NTA
CTO
R P
.C. B
OA
RD
AS
SEM
BLY
LN-2
5
6 PIN RECEPTACLE
HEXFET TRANS. (SS)
HEXFET TRANS. (SS)
33.2 OHM 1/4W.
CMOS MC14538B (SS)
.25
03.25
3.50 ~.04
0
.55
3.80
5.00~.04
XXXX X X X
XXX
XX
XX
R35
R34
R27
R17
R10
R15
R22
R21
R28
R26
R25
R13
R12
R9
R7
R6
R23
R5
R20
R24
R4 R
14 R16
R11
R3
R2
D3
C4
C13
C10
C8
C9
C7
C6
C11
C2
C3 C
5
C1
D1
DZ2
DZ1
D8
D2
D6
D5
D4
X5
X3
J9
J7
J6
R19
R1
R30
Q1
Q5
Q8
Q4
Q3
Q2
Q7
Q6
R18
R29
X4
X1
X2
R31
R32
L9670-1
G-16R
etur
n to
Sec
tion
TO
CR
etur
n to
Sec
tion
TO
CR
etur
n to
Sec
tion
TO
CR
etur
n to
Sec
tion
TO
C
Ret
urn
to M
aste
r T
OC
Ret
urn
to M
aste
r T
OC
Ret
urn
to M
aste
r T
OC
Ret
urn
to M
aste
r T
OC
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 pro-vided for 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 themachine.
ELECTRICAL DIAGRAMS G-17
PC BOARD ASSEMBLY-CONTACTOR - BELOW CODE 9900
CAPACITORS = MFD/VOLTS
ITEM REQ’D PART NO. IDENTIFICATION
INDUCTANCE = HENRYS
9185-2 3
-25-
94H
7-
8-94
D
1-1
3-95
D
2-2
0-98
C
R.T
.
F
ULL
L9
185-
1
3
-10-
94
THE
LINC
OLN
ELEC
TRIC
CO.
CLE
VELA
ND
, OH
IO U
.S.A
.
EQ
UIP
.TY
PE
SC
ALE
SU
BJE
CT
DR
DA
TEC
HK
RE
F.S
UP
’S’D
’GS
HT.
NO
.L
L91
85-2
CO
NTA
CTO
R P
.C. B
OA
RD
AS
SEM
BLY
LN-2
5
6 PIN RECEPTACLE
HEXFET TRANS. (SS)
HEXFET TRANS. (SS)
33.2 OHM 1/4W.
CMOS MC14538B (SS)
.25
03.25
3.50 ~.04
0
.55
3.80
5.00~.04
XXXX X X X
XXX
XX
XX
CONTACTOR
L9185-2
G-17R
etur
n to
Sec
tion
TO
CR
etur
n to
Sec
tion
TO
CR
etur
n to
Sec
tion
TO
CR
etur
n to
Sec
tion
TO
C
Ret
urn
to M
aste
r T
OC
Ret
urn
to M
aste
r T
OC
Ret
urn
to M
aste
r T
OC
Ret
urn
to M
aste
r T
OC
Ret
urn
to S
ectio
n T
OC
Ret
urn
to S
ectio
n T
OC
Ret
urn
to S
ectio
n T
OC
Ret
urn
to S
ectio
n T
OC
Ret
urn
to M
aste
r T
OC
Ret
urn
to M
aste
r T
OC
Ret
urn
to M
aste
r T
OC
Ret
urn
to M
aste
r T
OC SVM ERROR REPORTING FORM
We need to know if there are errors in our manuals. We also value any suggestions as toadditional tests or procedures that would make this SVM a better tool for you.
If you discover new or different “Problems or Symptoms” that are not covered in the three col-umn troubleshooting chart, please share this information with us. Please include themachine’s code number and how the problem was resolved.
Thank You,Technical Services GroupLincoln Electric Co.22801 ST. Clair Ave.Cleveland, Ohio 44117-1199
