Hioki 3255-50 HiTESTER, Instruction Manual

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5
Safety Notes
This product conforms to the safety requirements for CAT III
600V, CAT II 1000V measurement products.
To ensure safe operation of measurement products, IEC
61010 establishes safety standards for various electrical envi-
ronments, categorized as CAT I to CAT IV, and called mea-
surement categories. These are defined as follows.
CAT I: Secondary electrical circuits connected to an AC elec-
trical 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, house-
hold 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).
Higher-numbered categories correspond to electrical environ-
ments with greater momentary energy, so a measurement
product designed for CAT III environments can endure
greater momentary energy than one designed for CAT II.
Using a measurement product in an environment designated
with a higher-numbered category than that for which the prod-
uct is rated could result in a severe accident, and must be
carefully avoided.
Never use a CAT I measuring product in CAT II, III, or IV envi-
ronments.
The measurement categories comply with the Overvoltage
Categories of the IEC60664 Standards.
Measurement categories
(Overvoltage categories)