Hioki IR4055, Instruction Manual

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Low Resistance Measurement (Model IR4056, IR4057, IR4058)
3.8 Low Resistance Measurement
(Model IR4056, IR4057, IR4058)
WARNING
Do not measure under a live circuit condition.
CAUTION
If active circuits are connected to the measuring object
circuit in parallel, the impedance and transient current of
the parallel circuit could cause measurement errors.
The comparator function can be used during low resistance
measurement. See “3.4 Comparator Function” (p. 29)
For accurate measurements, be sure to perform zero adjustment
before measuring, to cancel the wire resistance of the test leads.
Zero adjustment can be performed with readings of up to a
maximum of 3
Ω
. When the reading exceeds 3
Ω
, [Err 1] will be
displayed, and zero adjustment will not be possible.
Wire the instrument so that the wiring resistance is less than 3
Ω
.
In the following circumstances, repeat the zero adjustment
procedure:
• After changing test leads
• When the ambient temperature changes by 1°C or more
• After replacing the fuse