Mettler Toledo 0978 Installation and Service Manual

B15141500A

(8/00).00

0978

Tension Weigh

Module

Installation and Service

Manual

No part of this manual may be reproduced or transmitted in any form or by any means, electronic or

mechanical, including photocopying and recording, for any purpose without the express written

permission of Mettler-Toledo, Inc.

U.S. Government Restricted Rights: This documentation is furnished with Restricted Rights.

METTLER TOLEDO

Publication Revision History

An overview of this manual’s revision history is compiled below.

Publication Name: 0978 Tension Weigh Module Service Manual

Publication Part Number: 15141500A Publication Date: 9/97

Part Number Date Revisions

A15141500A 12/99 Updated drawings and part numbers with new clevis pin design. Removed Smart

Mode junction box information, warranty information, and junction box wiring

diagrams.

B15141500A 8/00 Added grounding strap to drawings and parts lists.

Declaration of conformity

Konformitätserklärung

Déclaration de conformité

Declaración de Conformidad

Conformiteitsverklaring

Dichiarazione di conformitá

We/Wir/Nous/Wij/Noi:Mettler-Toledo, Inc.

1150 Dearborn Drive

Worthington, Ohio 43085 USA

declare under our sole responsibility that the product,

erklären, in alleiniger Verantwortung, daß dieses Produkt,

déclarons sous notre seule responsabilité que le produit,

declaramos, bajo nuestra sola responsabilidad, que el producto,

verklaren onder onze verantwoordelijkheid, dat het product,

dichiariamo sotto nostra unica responsabilitá, che il prodotto,

Type/ Tipo: Analog Load Cells/ Celdas de Carga Analógicas

Models: 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 Erklärung bezieht, mitder/den folgenden Norm(en) oder Richtlinie(n) übereinstimmt.

Auquel se réfère cette déclaration est conforme à la (aux) norme(s) ou au(x) document(s) normatif(s).

Al que se refiere esta declaración 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 è conforme alla/e sequente/i norma/e o documento/i normativo/i.

CE Conformity / CE-Konformität / Conformité CE

90/384/EU Nonautomatic Balances and Scales / Nichteselbsttätige Waagen / Balances à Functionnement non automatique

Article 1.2.a.

Other Directives and Standards / Andere Richtlinien und Normen / Autres documents

corresponding 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 Measures

Worthington, Ohio USA

September, 1996 according to EN45014

INTRODUCTION

This publication is provided solely as a guide for individuals who have received Technical Training in

servicing the METTLER TOLEDO product.

Information about METTLER TOLEDO Technical Training can be obtained by writing, calling, or faxing:

METTLER TOLEDO

1900 Polaris Parkway

Columbus, Ohio 43240 USA

Phone: (614) 438-4511

Fax: (614) 438-4958

www.mt.com

WARNING!

This equipment generates, uses, and can radiate radio frequency energy and if not installed and used

properly, i.e., in accordance with the instructions manual, may cause harmful interference to radio

communications. It has been tested and found to comply with the limits for a Class A computing device

pursuant to Subpart J of Part 15 of FCC Rules, which are designed to provide reasonable protection

against such interference when operated in a commercial environment. Operation of this equipment in a

residential area is likely to cause interference to radio communications, in which case the user at his own

expense will be required to take whatever measures may be required to correct the interference.

METTLER TOLEDO RESERVES THE RIGHT TO MAKE REFINEMENTS OR

CHANGES WITHOUT NOTICE.

Precautions

WARNING

PERMIT ONLY QUALIFIED PERSONNEL TO SERVICE

THIS EQUIPMENT. USE CARE WHEN MAKING CHECKS,

TESTS, AND ADJUSTMENTS THAT MUST BE MADE

WITH POWER ON. FAILING TO OBSERVE THESE

PRECAUTIONS CAN RESULT IN BODILY HARM.

WARNING

FOR CONTINUED PROTECTION AGAINST SHOCK

HAZARD, CONNECT TO PROPERLY GROUNDED OUTLET

ONLY. DO NOT REMOVE THE GROUND PRONG.

WARNING

DISCONNECT ALL POWER TO THIS UNIT BEFORE

REMOVING THE FUSE OR SERVICING.

CAUTION

BEFORE CONNECTING/DISCONNECTING ANY INTERNAL ELECTRONIC

COMPONENTS OR INTERCONNECTING WIRING BETWEEN ELECTRONIC

EQUIPMENT, ALWAYS REMOVE POWER AND WAIT AT LEAST THIRTY (30)

SECONDS. FAILURE TO OBSERVE THESE PRECAUTIONS COULD RESULT IN

BODILY HARM OR DAMAGE TO OR DESTRUCTION OF THE EQUIPMENT.

CAUTION

OBSERVE PRECAUTIONS FOR HANDLING ELECTROSTATIC

SENSITIVE DEVICES.

READ this manual BEFORE

operating or servicing this

equipment.

FOLLOW these instructions

carefully.

SAVE this manual for future

reference.

DO NOT allow untrained

personnel to operate, clean,

inspect, maintain, service, or

tamper with this equipment.

ALWAYS DISCONNECT this

equipment from the power

source before cleaning or

performing maintenance.

CALL METTLER TOLEDO for parts,

information, and service.

CONTENTS

1Introduction.......................................................................................................1-1

Overview............................................................................................................................ 1-1

0978 Assembly Includes..................................................................................................... 1-1

Check Rods/Bumpers .......................................................................................................... 1-1

2Sizing Load Cells...............................................................................................2-1

Overview............................................................................................................................ 2-1

3Installation Guidelines .......................................................................................3-1

Instructions ........................................................................................................................ 3-1

4Installation Instructions......................................................................................4-1

Instructions ........................................................................................................................ 4-1

5Wiring Weigh Modules to Junction Box ...............................................................5-1

Analog Junction Box........................................................................................................... 5-1

DigiTOL Junction Box (DLC Mode) ....................................................................................... 5-3

IDNet Junction Box............................................................................................................. 5-5

6Calibration ........................................................................................................6-1

Overview............................................................................................................................ 6-1

Calibration with Test Weights.............................................................................................. 6-1

Calibration by Material Substitution Method......................................................................... 6-2

Calibration Using a Load Cell Simulator............................................................................... 6-2

7Routine Care and Maintenance ...........................................................................7-1

Overview............................................................................................................................ 7-1

8Troubleshooting .................................................................................................8-1

Isolate the Problem ............................................................................................................ 8-1

Check Wiring...................................................................................................................... 8-1

Check Load Cells................................................................................................................8-2

Check Mechanical Components ........................................................................................... 8-2

9Spare Parts List ................................................................................................. 9-1

Hardware US...................................................................................................................... 9-1

50 - 300 lb ........................................................................................................................ 9-1

500 - 3,000 lb ................................................................................................................... 9-1

5,000 - 10,000 lb .............................................................................................................. 9-2

Hardware SI ....................................................................................................................... 9-3

25 - 100 kg ....................................................................................................................... 9-3

200 - 1,000 kg ..................................................................................................................9-3

2,000 - 5,000 kg................................................................................................................9-4

10 Appendices......................................................................................................10-1

Appendix 1 ...................................................................................................................... 10-1

Appendix 2 ...................................................................................................................... 10-2

Certificate of Conformance .................................................................................................. 10-2

Appendix 3 .................................................................................................................... 10-11

Wiring Diagrams ............................................................................................................. 10-11

Appendix 4 .................................................................................................................... 10-12

Outline Dimensions.......................................................................................................... 10-12

Chapter 1: Introduction

Overview

(8/00) 1-1

1 Introduction

Overview

METTLER TOLEDO 0978 tension weigh modules for hopper and tank scales are

designed for installations requiring suspended mounting. The system safely tolerates

adverse loads commonly present in industrial weighing applications while providing

repeatable, accurate weighments.

The tension weigh module incorporates an NTEP or OIML Certified load cell, and

includes special mounting hardware to ensure that the load cell measures only the true

vertical 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 Assembly

Includes • 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/Bumpers

The suspended hopper/tank system requires no check rods or bumpers to provide an

accurate weighing system. In some applications, however, rods or bumpers may be

required (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 METTLER

TOLEDO distributor for design assistance.

Chapter 2: Sizing Load Cells

Overview

(8/00) 2-1

2 Sizing Load Cells

Overview

Use the following method to determine the most appropriate 0978 tension weigh module

system for your application:

1. Calculate the tank/hopper tare weight (weight of empty apparatus), plus attached

plumbing, 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 gross

tank/hopper weight.

4. Multiply the gross tank/hopper weight by 1.25, then divide that number by the total

number of cells to determine the minimum recommended load cell capacity. (The

1.25 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 outdoors

may be exposed to external forces

such as wind, updraft, etc. Consider

these forces when selecting a load

cell.

Load cell capacity must be larger

than the highest distributed load.

Chapter 3: Installation Guidelines

Instructions

(8/00) 3-1

3 Installation Guidelines

Instructions

WARNING

PERMIT ONLY QUALIFIED PERSONNEL TO SERVICE THIS

EQUIPMENT. EXERCISE CARE WHEN MAKING CHECKS,

TESTS, AND ADJUSTMENTS THAT MUST BE MADE WITH

POWER ON. FAILING TO OBSERVE THESE PRECAUTIONS

CAN RESULT IN BODILY HARM.

WARNING

USE SAFETY CHAINS OR RODS TO PREVENT VESSEL FROM FALLING IN CASE OF

COMPONENT FAILURE.

1. Place the load cells around the vessel so that each support point carries an equal

portion of the load.

2. If the weighing system is subject to horizontal movement, provide suitable check

rods 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 by

pinning, 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 hang

vertically (see Figure 3-3).

5. To maintain the system’s weighing accuracy, deflection of all scale support steel

must not exceed 1/16 inch under full working load.

6. Use flexible lines on all dead-to-live connections. Rigid line connections should be

long 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 are

supported by or from the vessel, platform, or hopper to simulate the actual load

distribution.

NOTE: Provide a means for hanging

test weights from the vessel before

beginning installation.

METTLER TOLEDO 0978 Tension Weigh Module Installation and Service Manual

(8/00)3-2

CAUTION

OVERLOADING LOAD CELLS AT ANY TIME AND FAILING TO INSTALL LOAD CELLS

AND ASSOCIATED PARTS IN STRICT CONFORMITY WITH THIS DOCUMENT MAY

RESULT IN LOAD CELL MALFUNCTION, WEIGHING INACCURACY, AND MAY

PERMANENTLY DAMAGE THE LOAD CELL.

Chapter 3: Installation Guidelines

Instructions

(8/00) 3-3

Figure 3-1: Plan View

Three-Module System

Four-Module System

Check Rod

Vertical Column

Check Rod

Vertical

Column

METTLER TOLEDO 0978 Tension Weigh Module Installation and Service Manual

(8/00)3-4

Figure 3-2: Overhead View

Figure 3-3: Mounting Detail

Backing Plate

Washer

Safety Rod

Double

Nuts

Backing Plate

To Load Cell

1/8”

Gap

Side of Vessel

Section A-A, Gusset Removed

AA

Chapter 4: Installation Instructions

Instructions

(8/00) 4-1

4 Installation Instructions

Instructions

1. 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 Rod

End Bearing

Jam Nut

Clevis

Grounding Strap

METTLER TOLEDO 0978 Tension Weigh Module Installation and Service Manual

(8/00)4-2

2. Connect each weigh module clevis to an appropriately sized threaded rod to

suspend 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

WARNING

USE SAFETY CHAINS OR RODS TO PREVENT VESSEL FROM FALLING IN

CASE OF COMPONENT FAILURE.

3. Make sure an appropriately sized jam nut is placed against the clevis to prevent the

threaded rod from turning.

4. Double-nut the safety rods on the top of the upper mount and the bottom of the

lower mount against a backing plate (see Figures 4-2 and 4-3).

Chapter 4: Installation Instructions

Instructions

(8/00) 4-3

Figure 4-2: Mounting Detail

Figure 4-3: Mounting Detail

Structural

Support

Backing Plate

Washer

Safety Rod

Double

Nuts

Backing Plate

To Load Cell

Safety Rod

Backing

Plate

1/8”

Double

Nuts

Tank or

Hopper

Mounting

Bracket

Backing

Plate

Washer

METTLER TOLEDO 0978 Tension Weigh Module Installation and Service Manual

(8/00)4-4

5. Tack weld the backing plates into position after making sure that all weigh module

supports are hanging vertically (plumb).

6. The completed installation should resemble Figure 4-4. Make sure all support rods

are plumb. Ensure that all jam nuts are secure and that upper and lower rods are

double-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

Chapter 4: Installation Instructions

Instructions

(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

METTLER TOLEDO 0978 Tension Weigh Module Installation and Service Manual

(8/00)4-6

120º

90º

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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Mettler Toledo 0978 Installation and Service Manual

Mettler Toledo 0978 Installation and Service Manual

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