Hioki 3554, Инструкция по эксплуатации

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10.1 Effects of Extending the Measurement Lead
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The test lead extension is normally performed by Hioki. If you
want extension performed, contact your dealer or Hioki repre-
sentative.
Users should not extend the measurement leads.
Reducing Induced Voltage
Since the instrument measures a minute resistance with AC
power, it is affected by induced voltage. Induced voltage refers
to voltage that allows the current generated in the instrument to
build an inductive coupling in a lead and affect signal lines.
Since the phase of the induced voltage is shifted from that of the
AC current (reference signal) by 90 degrees, it can be eliminated
with the synchronous detection circuit if the voltage is low. But
for high levels, the induced voltage distorts the signals, causing
incorrect synchronous detection. The instrument monitors
induced voltage internally and generates an abnormal measure-
ment signal if the level rises above a certain level. Reducing the
length of the lead will lower induced voltage. Reducing the
length of the branched section is particularly effective. Even
when using the standard measurement lead, if in the 3 m
Ω
range the lead placement differs substantially between when the
zero-adjust feature was used and when the measurements were
taken, the effects of induced voltage will cause the values to
fluctuate by approximately 15 dgt.
Appendix
Chapter 10
10.1 Effects of Extending the Measure-
ment Lead and Induced Voltage