Hioki 3158 - Page 9

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Introduction
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DANGER
Indicates that incorrect operation presents an extreme hazard that
could result in serious injury or death to the user.
WARNING
Indicates that incorrect operation presents a significant hazard
that could result in serious injury or death to the user.
CAUTION
Indicates that incorrect operation presents a possibility of injury to the
user or damage to the product.
NOTE
Advisory items related to performance or correct operation of the product.
DANGER
･
Using a measuring instrument in an environment designated with a
higher-numbered category than that for which the instrument is rated
could result in a severe accident, and must be carefully avoided.
･
Never use a measuring instrument that lacks category labeling in a
CAT II to CAT IV measurement environment. Doing so could result in
a serious accident.
CAT II: When directly me as ur ing th e electrical outlet receptacles of t he p ri mar y
electrical circuits in e quip ment connected to a n AC electrical o utlet by a power
cord (portable tools, household appliances, etc.)
CAT I I I : When measuring the primary electrical circuits of heavy equipment (fixed
installations) connected directly to t he distribution panel, a nd feeders from the
distribution panel to outlets
CAT IV: When measurin g the circuit from the service drop to the service entrance, a nd to
the power met er a nd prima ry overcurrent protection device (distribution panel)
The following symbols in this manual indicate the relative importance of cautions
and warnings.
Measurement categories
To ensure safe operation of measuring instruments, IEC 61010 establishes safety
standards for various electrical environments, categorized as CAT II to CAT IV, and
called measurement categories.