B) Ac Current Measuring "A - VOLTCRAFT VC-519 Operating Instructions Manual

b) AC Current Measuring "A

Do not exceed the maximum permitted input values. Do not touch any circuits
or parts of circuits if they may be subject to voltages higher than 33 V/ACrms
or 70 V/DC! Danger to life!
The maximum permissible voltage in the measuring circuit against ground
potential must not exceed 600 V in CAT III.
Observe the required safety notes, provisions and safety measures for
intrinsic protection.
The current measurement takes place contact-free via the unfoldable current probe (2).
The sensors in the current probe record the magnetic field that is surrounded by conductors
through which current flows. A measurement is permitted on insulated as well as uninsulated
conductors and current rails. Ensure that the conductor always runs through the current probe
centred and that the current probe is always closed during measurement.
Always hold only one conductor with the current probe. If both the supply and return
conductors (e.g. L and N or plus and minus) are recorded, the currents will cancel each
other out and you will not get any measuring result. If several outer conductors are
recorded (e.g. L1 and L2), the currents will add up.
At very low currents, the conductor can be coiled
several times around a shank of the current probe to
increase the overall measuring current. Then divide
the measured current value by the number of coils
around the current probe. You will then receive the
correct current value.
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