Twilight DT4221, Инструкция пользователя

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7
Safety Notes
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.
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.
•
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.
This instrument conforms to the safety requirements for CAT III 600 V,
CAT IV 300 V measuring instruments.
CAT II: When directly measuring the electrical outlet receptacles of
the primary electrical circuits in equipment connected 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)
Distribution panel
Service entrance
Service drop
Internal wiring
CAT II
CAT IV
Po wer meter
CAT III
T
Outlet
Fixed installation
See: “2.3 Using Test Leads” (p. 24)