OHAUS CKW3R, Service Manual

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TABLE OF CONTENTS
CHAPTER 1 INTRODUCTION
Page No.
1.1 Introduction ................................................................................................................1-1
1.2
Service Facilities........................................................................................................1-1
1.3 Tools and Test Equipment Required .........................................................................1-2
1.4 Test Masses Required...............................................................................................1-2
1.5 Test Strategy .............................................................................................................1-2
1.6 Physical Description: Model CKW Bases ..................................................................1-2
1.7 Specifications.............................................................................................................1-3
1.8 How Load Cells Operate............................................................................................1-4
CHAPTER 2 TROUBLESHOOTING
2.1 Troubleshooting .........................................................................................................2-1
2.1.1 Checking Load Cells for Trouble ........................................................................2-1
CHAPTER 3 MAINTENANCE AND REPAIR PROCEDURES
3.1 Preventive Maintenance ............................................................................................3-1
3.1.1 Preventive Maintenance Checklist .....................................................................3-1
3.2 Replacing the Load Cell.............................................................................................3-1
3.3 Setting the Overload Stops........................................................................................3-2
CHAPTER 4 TESTING
4.1. Testing .......................................................................................................................4-1
4.2
Load Cell Resistance Checks....................................................................................4-1
4.3 Calibration with an External Indicator ........................................................................4-1
4.4. Consistency Check ....................................................................................................4-2
4.5 Performance Tests ....................................................................................................4-2
4.4.1 Shift Test ............................................................................................................4-3
4.4.2 Full Load Test.....................................................................................................4-3
CHAPTER 5 DRAWINGS AND PARTS LISTS
5-1 CKW Base Scale .......................................................................................................5-2
APPENDIX A: GLOSSARY
A-1 Glossary.................................................................................................................... A-1
LIST OF TABLES
1-1 Specifications for CKW Base Scales.....................................................................1-3
2-1 Load Cell Output Readings ...................................................................................2-2
4-1 Load Cell Resistance Readings ............................................................................4-1
4-2 Load Cell Output Readings ...................................................................................4-2
5-1 CKW Base Scale Parts List...................................................................................5-3
LIST OF ILLUSTRATIONS
1-1. Strain Gauge Load Cell .........................................................................................1-4
1-2 Downward force on the Platform bends the beam ................................................1-4
1-3 Route of electrical Load Cell input and output.......................................................1-5
3-1 CKW Load Cell, Spacer Down Stop Nuts and Jam Nuts ......................................3-2
4-1 Positions A, B, C and D are Centered...................................................................4-3
5-1 Exploded View of CKW Base ................................................................................5-2
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