5
Current Measurements: Application & Removal Of The Fork-clamp
Apply the Fork-clamp around conductor(s) of only one single pole of a circuit for load
current measurements. Applying around conductors of more than one pole of a circuit
may result in differential current (like identifying leakage current) measurements. Align
the conductor(s) to the Fork-clamp center indicators as
much as possible to get the
best measuring accuracy. For removal, remove the Fork-clamp from the conductor(s).
Adjacent current-carrying devices such as transformers, motors and conductor wires
may affect measurement accuracy. Keep the Fork-clamp away from them as much as
possible to minimize influence during measurements.
WARNING
This Fork-clamp meter series is designed to directly apply around or remove from
uninsulated hazardous live conductors. But still, individual protective equipment must
be used if hazardous live parts in the installation where measurement is to be carried
out could be accessible. Do not use the meter to measure currents above the rated
frequency (400Hz). Circulating currents may cause the magnetic circuits of the Fork-
clamp reach a hazardous temperature.
Fork-clamp ACA
Input is made via the Fork-clamp where best accuracy is specified at the center
indicator area.