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B15141500A(8/00).00
0978Tension WeighModuleInstallation and ServiceManual
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Mettler-Toledo, Inc. 1997, 1999, 2000
No part of this manual may be reproduced or transmitted in any form or by any means, electronic ormechanical, including photocopying and recording, for any purpose without the express writtenpermission of Mettler-Toledo, Inc.
U.S. Government Restricted Rights: This documentation is furnished with Restricted Rights.
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Declaration of conformityKonformittserklrung
Dclaration de conformitDeclaracin de Conformidad
Conformiteitsverklaring
Dichiarazione di conformitWe /Wir/Nous/Wij/Noi:Mettler-Toledo, Inc.1150 Dearborn DriveWorthington, Ohio 43085 USA
declare under our sole responsibility that the product,erklren, in alleiniger Verantwortung, da dieses Produkt,dclarons sous notre seule responsabilit que le produit,declaramos, bajo nuestra sola responsabilidad, que el producto,verklaren onder onze verantwoordelijkheid, dat het product,dichiariamo sotto nostra unica responsabilit, che il prodotto,
Type/ Tipo: Analog Load Cells/ Celdas de Carga AnalgicasModels: 736 (when used within the technical requirements listed in Test Certificate TC2826 and installed as a Load receptor as
listed in Type approval certificate T2206, Table 4.)
to which this declaration relates is in conformity with the following standard(s) or other normative document(s).auf das sich diese Erklrung bezieht, mitder/den folgenden Norm(en) oder Richtlinie(n) bereinstimmt.
Auquel se rfre cette dclaration est conforme la (aux) norme(s) ou au(x) document(s) normatif(s). Al que se refiere esta declaracin es conforme a la(s) norma(s) u otro(s) documento(s) normativo(s).Waarnaar deze verklaring verwijst, aan de volende norm(en) of richtlijn(en) beantwoordt.
A cui si riferisce questa dichiarazione conforme alla/e sequente/i norma/e o documento/i normativo/i.
CE Conformity / CE-Konformitt / Conformit CE 90/384/EU Nonautomatic Balances and Scales / Nichteselbst ttige Waagen / Balances Functionnement non automatique Article 1.2.a.Other Directives and Standards / Andere Richtlinien und Normen / Autres documentscorresponding to local requirements / entsprechend lokalen Anforderungen / correspondant aux exigences locales R60 OIML International Recommendation , Metrological regulation for load cells
Darrell Flocken, Manager - Weights & Measures
Office of Weights and MeasuresWorthington, Ohio USASeptember, 1996 according to EN45014
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INTRODUCTION
This publication is provided solely as a guide for individuals who have received Technical Training inservicing the METTLER TOLEDO product.
Information about METTLER TOLEDO Technical Training can be obtained by writing, calling, or faxing:
METTLER TOLEDO1900 Polaris ParkwayColumbus, Ohio 43240 USAPhone: (614) 438-4511Fax: (614) 438-4958 www.mt.com
WARNING!
This equipment generates, uses, and can radiate radio frequency energy and if not installed and usedproperly, i.e., in accordance with the instructions manual, may cause harmful interference to radiocommunications. It has been tested and found to comply with the limits for a Class A computing devicepursuant to Subpart J of Part 15 of FCC Rules, which are designed to provide reasonable protectionagainst such interference when operated in a commercial environment. Operation of this equipment in aresidential area is likely to cause interference to radio communications, in which case the user at his ownexpense will be required to take whatever measures may be required to correct the interference.
METTLER TOLEDO RESERVES THE RIGHT TO MAKE REFINEMENTS ORCHANGES WITHOUT NOTICE.
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Precautions WARNING
PERMIT ONLY QUALIFIED PERSONNEL TO SERVICETHIS EQUIPMENT. USE CARE WHEN MAKING CHECKS,TESTS, AND ADJUSTMENTS THAT MUST BE MADEWITH POWER ON. FAILING TO OBSERVE THESEPRECAUTIONS CAN RESULT IN BODILY HARM.
WARNINGFOR CONTINUED PROTECTION AGAINST SHOCKHAZARD, CONNECT TO PROPERLY GROUNDED OUTLETONLY. DO NOT REMOVE THE GROUND PRONG.
WARNINGDISCONNECT ALL POWER TO THIS UNIT BEFOREREMOVING THE FUSE OR SERVICING.
CAUTIONBEFORE CONNECTING/DISCONNECTING ANY INTERNAL ELECTRONICCOMPONENTS OR INTERCONNECTING WIRING BETWEEN ELECTRONICEQUIPMENT, ALWAYS REMOVE POWER AND WAIT AT LEAST THIRTY (30)SECONDS. FAILURE TO OBSERVE THESE PRECAUTIONS COULD RESULT INBODILY HARM OR DAMAGE TO OR DESTRUCTION OF THE EQUIPMENT.
CAUTIONOBSERVE PRECAUTIONS FOR HANDLING ELECTROSTATICSENSITIVE DEVICES.
READ this manual BEFORE
operating or servicing thisequipment.
FOLLOW these instructionscarefully.
SAVE this manual for futurereference.
DO NOT allow untrainedpersonnel to operate, clean,inspect, maintain, service, ortamper with this equipment.
ALWAYS DISCONNECT thisequipment from the powersource before cleaning orperforming maintenance.
CALL METTLER TOLEDO for parts,information, and service.
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CONTENTS
1 Introduction.......................................................................................................1-1Overview............................................................................................................................ 1-10978 Assembly Includes..................................................................................................... 1-1Check Rods/Bumpers .......................................................................................................... 1-1
2 Sizing Load Cells............................................................................................... 2-1Overview............................................................................................................................ 2-1
3 Installation Guidelines ....................................................................................... 3-1Instructions ........................................................................................................................ 3-1
4 Installation Instructions......................................................................................4-1Instructions ........................................................................................................................ 4-1
5 Wiring Weigh Modules to Junction Box ............................................................... 5-1Analog Junction Box........................................................................................................... 5-1DigiTOL Junction Box (DLC Mode)....................................................................................... 5-3IDNet Junction Box............................................................................................................. 5-5
6 Calibration ........................................................................................................6-1Overview............................................................................................................................ 6-1Calibration with Test Weights.............................................................................................. 6-1Calibration by Material Substitution Method......................................................................... 6-2
Calibration Using a Load Cell Simulator............................................................................... 6-2
7 Routine Care and Maintenance ...........................................................................7-1Overview............................................................................................................................ 7-1
8 Troubleshooting ................................................................................................. 8-1Isolate the Problem ............................................................................................................ 8-1Check Wiring...................................................................................................................... 8-1Check Load Cells................................................................................................................ 8-2Check Mechanical Components ........................................................................................... 8-2
9 Spare Parts List ................................................................................................. 9-1Hardware US...................................................................................................................... 9-1
50 - 300 lb ........................................................................................................................ 9-1500 - 3,000 lb ................................................................................................................... 9-15,000 - 10,000 lb .............................................................................................................. 9-2
Hardware SI ....................................................................................................................... 9-325 - 100 kg ....................................................................................................................... 9-3200 - 1,000 kg .................................................................................................................. 9-32,000 - 5,000 kg................................................................................................................ 9-4
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10 Appendices......................................................................................................10-1Appendix 1 ...................................................................................................................... 10-1Appendix 2 ...................................................................................................................... 10-2
Certificate of Conformance .................................................................................................. 10-2Appendix 3 .................................................................................................................... 10-11
Wiring Diagrams ............................................................................................................. 10-11
Appendix 4 .................................................................................................................... 10-12Outline Dimensions.......................................................................................................... 10-12
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Chapter 1: IntroductionOverview
(8/00) 1-1
1 Introduction
OverviewMETTLER TOLEDO 0978 tension weigh modules for hopper and tank scales aredesigned for installations requiring suspended mounting. The system safely toleratesadverse loads commonly present in industrial weighing applications while providingrepeatable, accurate weighments.
The tension weigh module incorporates an NTEP or OIML Certified load cell, andincludes special mounting hardware to ensure that the load cell measures only the truevertical load.
Individual weigh modules allow maximum application flexibility. Hoppers and tanks of
most sizes and shapes are easily suspended. Each tension weigh module has excellent inherent side-load rejection characteristics to compensate for non-axial loading.
0978 AssemblyIncludes
Clevis pins Clevis
Jam nuts Rod ends Hair-pin cotters Grounding strap Load cell Analog J-Box (standard) 0978 Tension Weigh Module Service Manual
Check Rods/BumpersThe suspended hopper/tank system requires no check rods or bumpers to provide anaccurate weighing system. In some applications, however, rods or bumpers may berequired (see Figures 3-1 and 3-2) to prevent movement that could cause misalignment of valves and gates, or slow settling times. Contact your local authorized METTLERTOLEDO distributor for design assistance.
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Chapter 2: Sizing Load CellsOverview
(8/00) 2-1
2 Sizing Load Cells
OverviewUse the following method to determine the most appropriate 0978 tension weigh modulesystem for your application:
1. Calculate the tank/hopper tare weight (weight of empty apparatus), plus attachedplumbing, agitators, vibrators, external forces, etc.
2. Estimate the maximum weight of the tank/hopper contents (net product weight).
3. Use the sum of the empty weight and the net weight to arrive at the grosstank/hopper weight.
4. Multiply the gross tank/hopper weight by 1.25, then divide that number by the totalnumber of cells to determine the minimum recommended load cell capacity. (The1.25 factor is an allowance for low-tare estimates and unequal load distribution.)Minimum Load Cell Capacity = 1.25 gross capacity/number of cells.
NOTE: A vessel situated outdoorsmay be exposed to external forcessuch as wind, updraft, etc. Considerthese forces when selecting a loadcell.
Load cell capacity must be largerthan the highest distributed load.
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Chapter 3: Installation GuidelinesInstructions
(8/00) 3-1
3 Installation Guidelines
Instructions
WARNINGPERMIT ONLY QUALIFIED PERSONNEL TO SERVICE THISEQUIPMENT. EXERCISE CARE WHEN MAKING CHECKS,TESTS, AND ADJUSTMENTS THAT MUST BE MADE WITHPOWER ON. FAILING TO OBSERVE THESE PRECAUTIONSCAN RESULT IN BODILY HARM.
WARNINGUSE SAFETY CHAINS OR RODS TO PREVENT VESSEL FROM FALLING IN CASE OFCOMPONENT FAILURE.
1. Place the load cells around the vessel so that each support point carries an equalportion of the load.
2. If the weighing system is subject to horizontal movement, provide suitable checkrods to limit horizontal movement to less than 1/8 inch (see Figures 3-1 and 3-2).
3. Prevent nuts on support bolts or at both ends of the support rods from turning bypinning, staking, or other means.
4. The use of top and bottom backing plates allows for fit-up during installation. Tack weld the backing plates in place after verifying that all cell assemblies hangvertically (see Figure 3-3).
5. To maintain the systems weighing accuracy, deflection of all scale support steelmust not exceed 1/16 inch under full working load.
6. Use flexible lines on all dead-to-live connections. Rigid line connections should belong enough to deflect without contributing weighing error.
7. Properly vent the tank or hopper system to prevent pressure imbalances.
8.
If test weights are to be used, distribute them evenly, making sure they aresupported by or from the vessel, platform, or hopper to simulate the actual loaddistribution.
NOTE: Provide a means for hangingtest weights from the vessel beforebeginning installation.
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METTLER TOLEDO 0978 Tension Weigh Module Installation and Service Manual
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CAUTIONOVERLOADING LOAD CELLS AT ANY TIME AND FAILING TO INSTALL LOAD CELLSAND ASSOCIATED PARTS IN STRICT CONFORMITY WITH THIS DOCUMENT MAYRESULT IN LOAD CELL MALFUNCTION, WEIGHING INACCURACY, AND MAY
PERMANENTLY DAMAGE THE LOAD CELL.
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Chapter 3: Installation GuidelinesInstructions
(8/00) 3-3
Figure 3-1: Plan View
Three-Module System
Four-Module System
Check Rod
Vertical Column
Check Rod
Vertical
Column
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METTLER TOLEDO 0978 Tension Weigh Module Installation and Service Manual
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Figure 3-2: Overhead View
Figure 3-3: Mounting Detail
Backing Plate
Washer
Safety Rod
DoubleNuts
Backing Plate
To Load Cell
1/8
Gap
Side of Vessel
Section A-A, Gusset Removed
A A
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Chapter 4: Installation InstructionsInstructions
(8/00) 4-1
4 Installation Instructions
Instructions1. Confirm that the tension weigh module system is complete. Refer to Figure 4-1 and
the spare parts list in Chapter 9.
Figure 4-1: Single Weigh Module Assembly
Clevis Pin
Hair-Pin Cotter
Jam Nut
Load Cell
Spherical RodEnd Bearing
Jam Nut
Clevis
Grounding Strap
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METTLER TOLEDO 0978 Tension Weigh Module Installation and Service Manual
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2. Connect each weigh module clevis to an appropriately sized threaded rod tosuspend the vessel. See Table 4-1 for clevis thread sizes.
0978 Weigh Module Capacity Clevis Thread Size
50 - 300 lb 3/8-16 UNC
500 - 3,000 lb 3/4-10 UNC
5,000 - 10,000 lb 1-8 UNC
25 - 100 kg M8 x 1.25
200 - 1,000 kg M12 x 1.75
2,000 - 5,000 kg M24 x 2
Table 4-1: Clevis Thread Sizes
WARNINGUSE SAFETY CHAINS OR RODS TO PREVENT VESSEL FROM FALLING INCASE OF COMPONENT FAILURE.
3. Make sure an appropriately sized jam nut is placed against the clevis to prevent thethreaded rod from turning.
4. Double-nut the safety rods on the top of the upper mount and the bottom of thelower mount against a backing plate (see Figures 4-2 and 4-3).
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Chapter 4: Installation InstructionsInstructions
(8/00) 4-3
Figure 4-2: Mounting Detail
Figure 4-3: Mounting Detail
StructuralSupport
Backing Plate
Washer
Safety Rod
DoubleNuts
Backing Plate
To Load Cell
To Load Cell
Safety Rod
BackingPlate
1/8
DoubleNuts
Tank orHopper
MountingBracket
BackingPlate
Washer
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METTLER TOLEDO 0978 Tension Weigh Module Installation and Service Manual
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5. Tack weld the backing plates into position after making sure that all weigh modulesupports are hanging vertically (plumb).
6. The completed installation should resemble Figure 4-4. Make sure all support rodsare plumb. Ensure that all jam nuts are secure and that upper and lower rods aredouble-nutted against supports.
NOTE: Check each weigh module to make sure that the grounding strap is not touching the load cell.
7. Refer to Figures 4-5 through 4-7 for various installation configurations.
Figure 4-4: Complete Installation
Typical Support Structure
Stiffener Plates
Stiffener Plate
Backing Plate
Double Nuts
Locking Jam Nut (Table 4-1)
Tank or Hopper
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Chapter 4: Installation InstructionsInstructions
(8/00) 4-5
Figure 4-5: Tank Supported with One Load Cell
Figure 4-6: Tank Supported with Two Load Cells
Safety Wire Rope
Safety Chain
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120
120 120
90
90 90
90
Three Support Plan View Four Support Plan View
Figure 4-7: Tanks Supported with Three or Four Load Cells
Safety Rod
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Chapter 5: Wiring Weigh Modules to Junction BoxAnalog Junction Box
(8/00) 5-1
5 Wiring Weigh Modules to Junction Box
Analog Junction BoxUse the wiring code tables provided to connect the load cells and instrument to theanalog junction box terminals.
Instrument
Function Color
+Excitation White
+Sense Yellow
+Signal Green
Shield Orange
-Signal Black
-Sense Red
-Excitation Blue
Load Cells
Function Color
+Excitation Green
-Excitation Black
+Signal White
-Signal Red
Shield Yellow
Table 5-1: Junction Box Wiring
Turn all potentiometers fullyclockwise prior to calibration.
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METTLER TOLEDO 0978 Tension Weigh Module Installation and Service Manual
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Figure 5-1: Junction Box Wiring
+SIG+EXE
-SIGSHLD
+SIG+EXE
-SIGSHLD
LC2
+EXE
SHLD-SIG
-EXE
+SIG
LC4
INPUT
+EXE+SIGSHLD-SEN
-SIG-EXE+SEN
TO INDICATOR
+EXE
SHLD-SIG
-EXE
+SIG
LC1
LC3
-EXE- EXE
To input terminal of second J-Box PCB for 5 8 cellsystems.
Individual load cell trimmingpotentiometers. If trimming isnecessary, trim the high output cells down to the lowest.
LoadCell 2
LoadCell 4
LoadCell 3
LoadCell 1
AnalogPCB
Analog Junction Box
Aux
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Chapter 5: Wiring Weigh Modules to Junction BoxDigiTOL Junction Box (DLC Mode)
(8/00) 5-3
DigiTOL Junction Box(DLC Mode)
WARNINGDO NOT USE THE DigiTOL JUNCTION BOX INLOCATIONS CLASSIFIED HAZARDOUS BY THENATIONAL ELECTRICAL CODE (NEC) ARTICLE 500.
The Model 0978 instrument uses a DigiTOL junction box to convert each load cell output into a digital signal. Only DigiTOL indicators work with the DigiTOL junction box.
In the DLC mode, the indicator acts as the host for the DigiTOL junction box, allowingyou to adjust scale parameters via the indicator keypad. See Tables 5-2 and 5-3 forcable connections and Figure 5-2 for PCB details.
Terminal Number Position Function Wire Color
TB2 10 +20 VDC Green
TB2 12 Ground Blue
TB1 1 Shield Orange
TB1 2 RXD A Red
TB1 3 RXD B White
TB1 4 TXD B Yellow
TB1 5 TXD A Black
Table 5-2: DigiTOL Junction Box Wiring DLC Mode
Function Color
+Excitation Green
+Signal White
Shield Yellow
-Excitation Black
-Signal Red
Table 5-3: Load Cell Color Codes (Code shown is for tension load)
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METTLER TOLEDO 0978 Tension Weigh Module Installation and Service Manual
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Figure 5-2: PCB Detail
51 TB1
1TB21
W3+EXC
LC 3
W1
-SIGCGND
-EXC
+SIG+EXC
W4
-SIGCGND
-EXC
LC 4
W2
+SIG
LC 1+SIG
CGND
-SIG-EXC
+SIG
CGND
-SIG
-EXC
LC 2
+EXC+EXC
See indicatorconnection notes
Note 1Note 2
Note 1: Jumper signal on any unusedload cell terminals.
Note 2: Jumpers W1 through W4 are set to match the load cell output type (Factoryset "ON"): ON - 2mV/V load cells OFF - 3mV/V load cells
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Chapter 5: Wiring Weigh Modules to Junction BoxIDNet Junction Box
(8/00) 5-5
IDNet Junction Box
Figure 5-3: Default Factory Setting
Jumper Status Description
W1 Closed Matching the gain at 2 mV/V load cells
W2 Closed No external sensing (-SEN)
W3 Closed No external sensing (+SEN)
W4 Closed Internal reference voltage = 3.5 V
W5 Open Excitation voltage for load cells = 4.0 V
W6 Closed Internal supply voltage = 7.1 V
W7 2 3 Protocol IDNet W8 1 2 Interface 20 mA
W9 Open Supply voltage IDNet
SA1 Closed Trim Potentiometers Circuit Disabled
Table 5-4: IDNet Junction Box Wiring and Default Factory Setting
TerminalCell + Excitation
Green- Excitation
Black +SignalWhite
-SignalRed
#1 4 4 9 9#2 3 3 8 8#3 2 2 7 7#4 1 1 6 6
- S E N
+ S E N
- E X C +
E X C
- S I G
+ S I G
P 3
P 5
W 6
W 8 W 7W4
W 3 W 2W 5
P 7 P 8
P1 P2
ST 2 ST 3
SA 1
87654321
LC 4
LC 3
LC 2
LC 1
W 1
W 9
Indicator Plug
LC3&4 GroundStandoff
LC1&2 GroundStandoff
1
2
3
4
5
6
7
8
9
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Chapter 6: CalibrationOverview
(8/00) 6-1
6 Calibration
Overview
WARNINGPERMIT ONLY QUALIFIED PERSONNEL TO SERVICE THISEQUIPMENT. EXERCISE CARE WHEN MAKING CHECKS,TESTS, AND ADJUSTMENTS THAT MUST BE MADE WITHPOWER ON. FAILING TO OBSERVE THESE PRECAUTIONSCAN RESULT IN BODILY HARM.
After installing the weigh modules and the instrument, you must calibrate the system. If the scale is used for legal trade (buying and selling) purposes, calibrate it with certifiedtest weights traceable to a recognized standard.
Plan provisions for calibration in advance: Always contact the local Weights andMeasures authorities prior to any scale installation to verify exact requirements forcalibration and certification.
To achieve maximum accuracy and Weights and Measures authorities approval,perform the final check using approved test weights. In certain instances, a combinationof test weights and material in the tank or hopper can be built up to the necessary
weight.
Calibration with TestWeights
1. Remove all weight from the vessel.
2. Zero the indicator (follow manufacturers instructions).
3. Evenly distribute the test weights on the vessel. For best results, test weights shouldequal or approach scale capacity.
4. Adjust the indicator until it reads the weight applied to the vessel.
5. Remove the test weights and check the return to zero. Adjust if necessary.
6. Re-apply the weights to verify the calibration.
NOTE: Refer to the proper users guidefor calibration procedures for yourdigital indicator.
If the hopper or tank is located highabove the floor, it may be feasible tosuspend test weights from below. If the tank or hopper is situated close tothe floor and you must place the test
weights on the structure, you mayneed to provide brackets or shelvesfor safety.
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Chapter 7: Routine Care and MaintenanceOverview
(8/00) 7-1
7 Routine Care and Maintenance
OverviewOnce you install the scale, you should periodically inspect and calibrate the assembly.
If the scale is used for legal-for-trade purposes, consult the local Weights and Measuresauthority for minimum inspection requirements. Contact your authorized METTLERTOLEDO representative for information on periodic inspection and calibration services.
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Chapter 8: TroubleshootingIsolate the Problem
(8/00) 8-1
8 Troubleshooting
Isolate the Problem
WARNINGPERMIT ONLY QUALIFIED PERSONNEL TO SERVICE THISEQUIPMENT. EXERCISE CARE WHEN MAKING CHECKS,TESTS, AND ADJUSTMENTS THAT MUST BE MADE WITHPOWER ON. FAILING TO OBSERVE THESE PRECAUTIONSCAN RESULT IN BODILY HARM.
To determine whether the problem is in the scale assembly or the indicator:
1. Remove power from the system.
2. Disconnect the 0978 scale assembly and connect an analog load cell simulator tothe indicator (analog simulator available from METTLER TOLEDO).
3. Reapply power and test.
4. If the problem persists, consult the indicator manual for further troubleshootingassistance.
If the problem is NOT present with the load cell simulator attached to the indicator:
1. Remove power.
2. Disconnect the simulator, and reconnect the 0978 scale assembly.
3. If the problem re-occurs, further scale assembly troubleshooting is required.
Check Wiring1. Remove power from the system.
2. Remove the cover from the junction box and check the interior for moisture,corrosion, or any foreign material.
3. Ensure that all wiring connections are tight and that no insulation material istouching the terminal contacts. Check all cable connections for correct wiring. The
wiring color codes for Analog and DLC modes are provided in Chapter 5.
4. Check all cable connectors on the junction box. Tighten any loose connectors.
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METTLER TOLEDO 0978 Tension Weigh Module Installation and Service Manual
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Check Load Cells1. Remove power from the system. Fully disconnect each load cell and check for
proper input/output resistances (see Table 8-1).
Measuring Points Resistance Any lead to shield or ground Infinity
+Exc (Green) to -Exc (Black) 350 Ohm minimum
+Signal (White) to -Signal (Red) 347 to 353 Ohms
Table 8-1: Load Cell Resistance
2. If resistance is within specification, perform a shorted-signal symmetry test. Short the signal leads together and place one multimeter lead on the shorted
signals and one lead on the +Excitation wire. Note the resistance value.
Remove the lead from the +Excitation wire and place it on the Excitation wire.The two resistance values should be approximately equal.
3. If the load cells pass the shorted-signal test, reconnect them and reapply power tothe scale. Confirm that the proper excitation voltage is reaching the load cells byplacing multimeter leads on the excitation positions of each load cell terminal.
4. If proper excitation voltage is reaching the load cells, check the output signal fromeach cell by disconnecting the signal leads and measuring voltage output. If onecell has a particularly high or low dead-load output, it is suspect. The maximumoutput possible from any cell is 30 mV at 15 VDC excitation and loaded to grosscapacity.
5. If any load cell has an unusual signal, remove all load from that cell.
With the power on, measure the output from the suspect load cell. The no-loadzero output should be 1.0% of the full scale output. For example, if theexcitation voltage is 15 VDC, then the full scale output would be 30 mV andthe no-load zero output should be within 0.3 mV.
6. If a load cell fails any of the above tests, replace it.
Check MechanicalComponents
Due to the simplicity of the 0978 weigh modules, there are few mechanical componentsto troubleshoot: Make sure the safety rods are plumb (hanging vertically). Tighten all jam nuts. Check for wear or damage at rod end bearings, clevis pins, or clevis brackets. Check for any environmental influences such as wind, temperature, or vibrations. Check for mechanical binds in the piping connections, etc.
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Chapter 9: Spare Parts ListHardware US
(8/00) 9-1
9 Spare Parts List
Hardware US
50 - 300 lbItem Qty. Part Number Description
1 2 TN800744 Clevis Pin3/8 x 1.25
2 2 TN600892 Clevis
3 1 TN600903 Grounding Strap4 2 MZ0901020036 Nut 3/8-24
5 2 MZ0901040014 Rod End3/8-24 RH
6 2 MZ0904000006 Hair-Pin Cotter
7 2 MZ0901010155 Screw 10-32
500 - 3,000 lbItem Qty. Part Number Description
1 2 TN800745 Clevis Pin1/2 x 1.75
2 2 TN600893 Clevis3 1 TN600903 Grounding Strap
4 2 MZ0901020039 Nut 1/2-20
5 2 MZ0901040013 Rod End1/2-20 RH
6 2 MZ0904000006 Hair-Pin Cotter
7 2 MZ0901010155 Screw 10-32
1
4
6
2
S-Cell
5
3
7
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5,000 - 10,000 lb
Item Qty. Part Number Description
1 2 TN800746 Clevis Pin3/4 x 2.50
2 2 TN600894 Clevis
3 1 TN600903 Grounding Strap
4 2 MZ0901020038 Nut 3/4-16
5 2 MZ0901040013 Rod End3/4-16 RH
6 2 MZ0904000077 Hair-Pin Cotter
7 2 MZ0901010155 Screw 10-32
Load Cells
Capacity (lb) Class III 3kd
50 lb TA600238
100 lb TA600240
200 lb TA600242
300 lb TA600244
500 lb TA600246
1,000 lb TA600250
2,000 lb TA6002523,000 lb TA600254
5,000 lb TA600256
10,000 lb TA600258
Table 9-1: Spare Parts List (U.S. Units)
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METTLER TOLEDO 0978 Tension Weigh Module Installation and Service Manual
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2,000 - 5,000 kg
Item Qty Part Number Description
1 2 TN600558 Clevis Pin 25 mm
2 2 TN600555 Clevis 25 mm M24 x 2
3 1 TN600903 Grounding Strap4 4 MZ0901020096 Nut, Hex Jam
M24 x 2 NI
5 2 MZ0901040019 Rod-End 25 mmM24 x 2 M RH
6 2 MZ0904000073 Hair-Pin Cotter #6
7 2 MZ0901010489 Screw M4 x 0.7
Load Cells
Capacity (kg) Class III 3kd
25 kg TA600536
50 kg TA600537
100 kg TA600538
200 kg TA600539
500 kg TA600540
1,000 kg TA600541
2,000 kg TA6005425,000 kg TA600543
Table 9-2: Spare Parts (SI Units)
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Chapter 10: AppendicesAppendix 1
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10 Appendices
Appendix 1
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Appendix 2
Certificate of Conformance
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Chapter 10: AppendicesAppendix 2
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Chapter 10: AppendicesAppendix 2
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Chapter 10: AppendicesAppendix 2
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Chapter 10: AppendicesAppendix 2
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Chapter 10: AppendicesAppendix 3
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Appendix 3
Wiring DiagramsReference Drawings
TB100505 Analog Systems
TB100575 DigiTOL Systems
TB100600 IDNet
NOTE: Contact MTMS document supervisor for latest drawing revision.
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Appendix 4
Outline Dimensions
Load Cell Capacity A B C D
50 lb - 300 lb 7 5/8" 2" 1 3/8" 3/8-16 UNC
500 lb - 3,000 lb 10 9/16" 2 1/4" 1 7/8" 3/4-10 UNC
5,000 lb 12 5/8" 2 3/4" 2 3/4" 1-8 UNC
10,000 lb 12 5/8" 3" 2 3/4" 1-8 UNC
25 kg - 100 kg 180 mm 50.8 mm 32 mm M8 x 1.25
200 kg - 1,000 kg 250 mm 57.2 mm 49 mm M12 x 1.75
2,000 kg 450 mm 69.9 mm 83 mm M24 x 2
5,000 kg 450 mm 76.2 mm 83 mm M24 x 2
Figure 10-1
A (Nominal)LoadCell
B C
D
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