Hioki PW3336-01, Instruction Manual

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Safety Information
4
Notation
Accuracy
We define measurement tolerances in terms of f.s. (full scale), rdg. (reading) and dgt. (digit) values, with the
following meanings:
Measurement categories
To ensure safe operation of measuring instruments, IEC 61010 establishes safety standards for various elec-
trical environments, categorized as CAT II to CAT IV, and called measurement categories.
This instrument conforms to the safety requirements for CAT II 1000 V, CAT III 600 V measuring instruments.
Indicates the prohibited action.
(p. ) Indicates the location of reference information.
* Indicates that descriptive information is provided below.
SET
(Bold character)
Names of settings, buttons, and other screen elements are enclosed in brackets.
The screen of this instrument displays characters in the following manner.
f.s. (range) This is usually the name of the currently selected range.
rdg. (reading or displayed value) The value currently being measured and indicated on the measuring instrument.
dgt. (resolution)
The smallest displayable unit on a digital measuring instrument, i.e., the input val-
ue that causes the digital display to show a "1" as the least-significant digit.
• 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.
• Using a measuring instrument without categories in an environment designated with
the CAT II to CAT IV category could result in a severe accident, and must be carefully
avoided.
CAT II
When directly measuring the electrical outlet receptacles of the primary electrical circuits in equipment con-
nected to an AC electrical outlet by a power cord (portable tools, household appliances, etc.)
CAT III
When measuring the primary electrical circuits of heavy equipment (fixed installations) connected directly to
the distribution panel, and feeders from the distribution panel to outlets.
CAT IV
When measuring the circuit from the service drop to the service entrance, and to the power meter and primary
overcurrent protection device (distribution panel).