Hioki MO HiTESTER 3452, Instruction Manual

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Safety Notes
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CAT I : Secondary electrical circuits
connected to an AC electrical
outlet through a transformer or
similar device.
CAT II : Primary electrical circuits in
equipment connected to an AC
electrical outlet by a power cord
(portable
tools, household
appliances, etc.)
CAT III : Primary electrical circuits of heavy
equipment (fixed installations)
connected directly to the
distribution panel, and feeders from
the distribution panel to outlets.
CAT IV : The circuit from the service drop to
the service entrance, and to the
power
meter and primary
overcurrent protection device
(distribution panel).
Measurement categories (Overvoltage
categories)
This instrument complies with CAT III safety
requirements.
To ensure safe operation of measurement
instruments, IEC 61010 establishes safety
standards for various electrical environments,
categorized as CAT I to CAT IV, and called
measurement categories. These are defined as
follows.