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2. USE
Current clamps are used to measure the current flowing in a cable without having
to open the circuit. They are also used to insulate the user from dangerous volt‑
ages in the circuit.
The clamps can be used with the installation testers to make current measure‑
ments, selective earth measurement on live circuit, power measurements and the
decomposition of the signals measured into harmonics.
The choice of clamp to use depends on the function, the current value that is to be
measured and the diameter of the cables.
Clamp
MN77
C177A
Transformation ratio
1000/1
10 000/1
Measurement range
0.005 ‑ 20 A
0.05 ‑ 200 A
Clamping diameter
20 mm
52 mm
Connect the clamp to the
terminal of the installation tester. The symbol
then appears on the bottom strip of the display unit of the instrument.
Press the trigger on the clamp to open the jaws.
Then clamp the cable that is to be measured. Where possible, the cable should
be centred in the jaws of the clamp.
Release the trigger.
For details of the measurement configuration, technical characteristics, er-
ror messages and memorisation, refer to the user manuals of the C.A 6113,
C.A 6116N or C.A 6117.
When the measurement has been made, press the trigger to open the clamp and
withdraw the cable from the jaws. Then disconnect the clamp from the instrument.
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