38
Repairs, Inspections, and Cleaning
Symptom
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When readings from the
instrument are compared
with those of another
clamp-on current meter, the
measured values differ.
The instrument cannot accurately measure waveforms that contain a
component that falls outside the frequency characteristics range.
Since the instrument performs true RMS measurement, it can accurately
measure distorted waveforms. When measuring a distorted waveform,
the measured value will differ from a clamp-on current meter that uses the
averaging method.
The current value is larger
than expected.
A current value is displayed
even though there is no
input.
The instrument cannot perform measurement accurately in the presence
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source such as a wireless device.
A sound is being emitted
by the instrument’s clamp
sensor.
The clamp sensor may emit sound when measuring AC currents in excess
of approx. 500 A, however, there is no effect on the measurement.
The measured value does
not appear.
No measured value is
displayed, even when the
test leads are shorted.
Zero adjustment is
impossible.
Check the continuity of the test leads. (p. 27)
If a wiring break is found, replace the test leads.
Insert the test leads all the way.
Use the proper measurement method.
If no problem can be found, the instrument may be damaged.
Send the instrument for repair.
When performing current measurement, perform zero-adjustment while no
measurement target is being clamped.
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