Chauvin Arnoux IMEG 500 Mode D'emploi page 23

At rest the needle should read zero on the voltmeter position: if not, reset it by
means of the central black screw (see descriptive diagram)
Connect the protective earth terminal (see descriptive diagram) to the protective
conductor (earth)
Do not connect the instrument to the terminals of a circuit of which the voltage
exceeds 600 V
Before measuring any resistance check that the circuit isn't live (switch to
voltmeter position before connecting)
After each insulation resistance measurement, allow the
circuit to discharge (a few seconds) before disconnecting the instrument
ADVICE ON USE ADVICE ON USE
ADVICE ON USE ADVICE ON USE ADVICE ON USE
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