background image

APPENDIX A  GLOSSARY 

APPENDIX A.

  

GLOSSARY 

Ohaus Load Cells contain a specification label on the Load Cell itself. 

Compensated Temperature Range 

The range of temperatures over which the output from the cell is compensated.  If used 
outside this range the output cannot be guaranteed to follow the specifications. 

 

Environmental Protection

 

IP rating against moisture and dust, for example, IP 65. 

 

Excitation

 

Voltage applied to the Exe+ and Exe– leads of the load cell. 

 

Input Resistance 

The resistance measured across Exe+ and Exe– with load cell disconnected and  
no load. 

 

Insulation Resistance

 

Normally measured at 50 V dc, this is the minimal resistance between the metal body of 
the load cell and any of its electrical connections. 

 

Mechanical Failure

 

The load at which the cell is likely to fail mechanically, that is, break or deform. 

 

mV/V 

Usually the output from a load cell will be approximately 0m V at zero load, though 
typically there may be a small offset voltage at zero load.  Over the full rated capacity of 
the load cell, the mV output will change.  The amount by which it changes depends upon 
the resistance change in the cell and on the excitation voltage applied.  Since the load 
cell manufacturer does not know what excitation voltage will be applied to the cell, rather 
than quote the V output over full range, they will quote the milli-Volt output per volt of 
excitation, or in its short form, mv/V. Most Ohaus Indicators provide an excitation voltage 
of 5 Volts dc. 

 

Output Resistance

 

The resistance measured across S+ plus and S– with load cell disconnected and  
no load. 

 

Overload Capacity

 

The maximum load that can be applied without permanent damage.  Loads in excess of 
maximum capacity will cause damage to the load cell. 

Rated Capacity

 

 

The maximum load over which the load cell will operate within its specifications. 

Rated Output

 

The nominal mV/V output of the load cell. 

 

Ultimate Capacity 

This is a percentage setting, usually 300% of full capacity. 

 

Zero Balance

 

The output of the load cell at no load, normally quoted as a percentage of full load.  Also 
known as zero offset. 

CKW Base Series Service Manual 

A-1 

Ohaus Corporation  www.ohaus.com 

Содержание CKW3R

Страница 1: ...SERVICE MANUAL CKW Bases Ohaus Corporation 19A Chapin Road P O Box 2033 Pine Brook NJ 07058 2033 973 377 9000...

Страница 2: ......

Страница 3: ...e of publication but Ohaus Corporation assumes no liability arising from the use or misuse of this material Reproduction of this material is strictly prohibited Material in this manual is subject to c...

Страница 4: ......

Страница 5: ...nce 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 C...

Страница 6: ...TABLE OF CONTENTS CKW Base Series Scales Service Manual ii Ohaus Corporation www ohaus com...

Страница 7: ...Maintenance Procedures Contains preventive maintenance procedures and disassembly repair and replacement procedures Chapter 4 Testing Contains guides for operational and performance tests and adjustm...

Страница 8: ...d Cells with connecting cable and hardware Each base contains the following basic replaceable assemblies Platform Load Cell with Connecting Cable and Down Stop and mounting hardware There is an explod...

Страница 9: ...2 lb 15 kg x 0 002 kg 30 lb x 0 005 lb 30 kg x 0 005 kg 60 lb x 0 01 lb Maximum Resolution 1 6000 1 7500 1 7500 1 6000 Capacity MAX x Approved Readability e 3 kg x 0 001 kg 6 lb x 0 002 lb 6 kg x 0 00...

Страница 10: ...Platform Strain Gauges Beam Printed Circuit Board completing Wheatstone Bridge circuit Holes drilled in Strain Gauge Load Cell Figure 1 1 Typical Strain Gauge Load Cell The strain gauges are wired in...

Страница 11: ...gnal is read by the Indicator which converts it to a numeric value and shows it visually This output value increases as weight is loaded to the Load Cell For example a 500kg Load Cell with 2mV V outpu...

Страница 12: ...CHAPTER 1 INTRODUCTION Ohaus Corporation www ohaus com 1 6 CKW Base Series Service Manual...

Страница 13: ...improper operation of the Base If the Down Stops are improperly set adjust them See Section 3 3 Check the metal surfaces of the Platform All surfaces should be parallel If the platform is deformed it...

Страница 14: ...CHAPTER 2 DIAGNOSTIC GUIDE Ohaus Corporation www ohaus com 2 2 CKW Base Series Service Manual...

Страница 15: ...the Platform CAUTION DO NOT USE CHEMICAL CLEANERS OR SOLVENTS OF ANY TYPE SOME CLEANERS ARE ABRASIVE AND MAY AFFECT THE SCALE S FINISH 3 Check the Load Cell cable for broken or damaged insulation 4 M...

Страница 16: ...load at each corner stop one at a time adjust the round Overload Stop Nut and lock it with the Jam Nut when the Upper Housing just touches the Overload Stop Nut 2 Repeat this for all four corners 3 Fo...

Страница 17: ...e Indicator and at no load when these tests are made In addition to the four resistance elements which make up the Wheatstone Bridge there are commonly one or two resistors in the excitation lines The...

Страница 18: ...red output readings with the theoretical values from the Load Cell data See Table 4 2 TABLE 4 2 LOAD CELL OUTPUT READINGS in mV with 5V Excitation Model Capacity Zero Load 50 Load 100 Load CKW3 3kg 4...

Страница 19: ...sted or replaced Prior to starting this test the Base must be connected to a properly functioning Indicator with capacity and readability values set according to the specifications for the Base under...

Страница 20: ...weight to point D and record the reading 7 If the reading at point A is negative file at points 1 and 4 AT AN ANGLE 8 If the reading at point B is negative file at points 1 and 2 STRAIGHT ACROSS 9 If...

Страница 21: ...n passed test the Base s full capacity according to the Specification Table 1 1 The Base must meet all specifications as listed 2 If the Base fails the Full Load Test check and set the Down Stops See...

Страница 22: ...CHAPTER 4 TESTING Ohaus Corporation www ohaus com 4 6 CKW Base Series Service Manual...

Страница 23: ...y checked after the replacement is made The base MUST meet the parameters of all applicable specifications in this manual If further technical information is needed please contact your local Ohaus off...

Страница 24: ...CHAPTER 5 PARTS LISTS DIAGRAMS 5 1 CKW CHECKWEIGHER BASES HOUSING PARTS Figure 5 1 CKW Checkweigher Base Housing Parts Ohaus Corporation www ohaus com 5 2 CKW Base Series Service Manual...

Страница 25: ...ad Set CKW Base set of 6 5 Load Cell Mounting Bolt 6 Load Cell 7 Load Cell Spacers 8 Level Bracket 10 Column Mount Bolt Kit 11 Down Stop Nut and Jam Nut When replacement parts are needed refer to the...

Страница 26: ...CHAPTER 5 PARTS LISTS DIAGRAMS Ohaus Corporation www ohaus com 5 4 CKW Base Series Service Manual...

Страница 27: ...ad Over the full rated capacity of the load cell the mV output will change The amount by which it changes depends upon the resistance change in the cell and on the excitation voltage applied Since the...

Страница 28: ...APPENDIX A GLOSSARY Ohaus Corporation www ohaus com A 2 CKW Base Series Service Manual...

Страница 29: ......

Страница 30: ...80252592 P N 80252592 SERVICE MANUAL CKW BASES...

Отзывы: