Hioki LR8431, Instruction Manual

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Safety Information
5
Measurement categories
To ensure safe operation of measurement instruments, IEC 61010 establishes safety stan-
dards for various electrical environments, categorized as CAT II to CAT IV, and called mea-
surement categories.
Using a measurement instrument in an environment designated with a higher-numbered cat-
egory than that for which the instrument is rated could result in a severe accident, and must
be carefully avoided.
Use of a measurement instrument that is not CAT-rated in CAT II to CAT IV measurement
applications could result in a severe accident, and must be carefully avoided.
Difference between "Measurement" and "Recording"
The measurement and recording processes are distinguished as follows for the purposes of
these instructions.
Measured data (data acquired in internal memory) is erased whenever a new measurement
starts. To retain data, always record (save) it.
CAT II
Primary electrical circuits in equipment connected to an AC electrical outlet
by a power cord (portable tools, household appliances, etc.)
CAT II covers directly measuring electrical outlet receptacles.
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:
The acquisition of input values into internal HiLogger memory or to a PC
via communications.
Recording:
Storing measurement data on a CF card, USB flash drive or on a PC via
data communication.