Voltmaster NCV 1 Mode D'emploi page 21

Definition of measurement categories.
Measurement category II:
Measurement category II is applicable to test and measuring
circuits connected directly to utilization points (socket outlets
and similar points) of the low-voltage mains installation. Typical
short-circuit current is < 10 kA.
Measurement category III:
Measurement category III is applicable to test and measuring
circuits connected to the distribution part of the building's low-
voltage mains installation. Typical short-circuit current is
< 50 kA.
Measurement category IV:
Measurement category IV is applicable to test and measuring
circuits connected at the source of the building's low-voltage
mains installation. Typical short-circuit current is >> 50 kA.
Read the instruction before use. If the equipment is used in a
manner not specified by the manufacturer, the protection pro-
vided by the equipment may be impaired.
All parts of the device and its accessories are not allowed to be
changed or replaced , other than authorized by the manufactur-
er or his agent.
For cleaning the unit, use a dry cloth.
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