PeakTech 3443 Operation Manual page 56

5.2. Voltage measurement (mV)
Caution!
Do not measure DC voltages if a motor on the circuit is being
switched ON or OFF. Large voltage surges may occur during the ON
or OFF operations that can damage the meter.
Caution!
Understanding Phantom readings:
In some DC and AC voltage ranges, when the test leads are not
connected to any circuit, the display might show a phantom reading.
This is normal. The meter's high input sensitivity produces a
wandering effect. When you connect the test leads to a circuit,
accurate reading appears.
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