Earth Resistance Clamp Meter
1. Switch off
2. Unscrew the screw on the battery cover
3. Remove the cover
4. Take the battery box out of the instrument
5. Replace new batteries of the same type
7. Reinstall the battery box
8. Replace the battery cover
9. Reinstall the screw
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Earth Resistance Clamp Meter
Application field
EARTH RESISTANCE CLAMP is designed for testing earth
resistance of any loop system, for example no only earth
resistance of electric power transportation conductors and
communication circuitry, but also earth resistance of electric
equipment and lightning arrester can be tested. When there
is a interference current in the grounding loop, the accuracy
of resistance measurement is affected, the interference
current can be tested by the earth resistance clamp.
Principle of mearsurement
Rx : earth resistance value to be tested
R1R2...Rn: multiple parallel earth resistance
Rearth: normally be regard as 0Ω
Rguard wire : normally be regard as 0Ω
RLoop=Rx+Rearth+(R1// R2//...Rn)+Rguard wire
When R1//R2//...Rn<<Rx, then RLoop=Rx
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