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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

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    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

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    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

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    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

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    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

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    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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    METTLER TOLEDO 0978 Tension Weigh Module Installation and Service Manual

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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

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    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)

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    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

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    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

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    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

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    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

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    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

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    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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    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

    (8/00) 10-3

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    Chapter 10: AppendicesAppendix 2

    (8/00) 10-5

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    Chapter 10: AppendicesAppendix 2

    (8/00) 10-7

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    Chapter 10: AppendicesAppendix 2

    (8/00) 10-9

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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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    METTLER TOLEDO1900 Polaris ParkwayColumbus, Ohio 43240 USA

    P/N: B15141500A

    METTLER TOLEDO is a trademark of Mettler-Toledo, Inc. 1997, 1999, 2000 Mettler-Toledo, Inc.Printed in U.S.A.

    B15141500A


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