Cutler-Hammer HWT-500, Инструкция по эксплуатации

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I.B. 35-557
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INTRODUCTION
The Cutler-Hammer type HWT-500 universal, portable network protector test set has been
designed for use on network protector breakers of all amperage ratings, 60HZ, and in the
voltage class of 480 and 216.
It is designed for electrical and mechanical testing of any network protector breaker, or
selected component parts, on voltages from 208Y/120 to 480Y/277 volts, three phase, four
wire wye connected systems, or 480 volt, three phase, three wire delta systems.
The primary purpose of this test set is for routine testing of network protector breakers and
calibration of network relays and electrical components in the field. However, if a network
protector or a simulated network protector breaker is used with this test set, scales of the
digital meters on the test set are such that network relays can be calibrated at a service
center or laboratory.
NOTE
VOLTAGES AT SERVICE CENTERS OR LABORATORIES MAY NOT BE EQUIVALENT IN
VOLTAGE MAGNITUDE OR VOLTAGE BALANCE BETWEEN PHASES AS COMPARED TO
THE VOLTAGES FOUND IN MOST NETWORK LOCATIONS. MOST ELECTRO-MECHANICAL
RELAYS ARE VOLTAGE SENSITIVE DEVICES WHOSE CALIBRATED SETTINGS CAN BE
AFFECTED BY VARIOUS SYSTEM VOLTAGE LEVELS. DUE TO THIS FACT, WE
STRONGLY RECOMMEND THAT THE FINAL RELAY CALIBRATION OF ELECTRO-
MECHANICAL RELAYS BE PERFORMED USING THE SYSTEM VOLTAGE AVAILABLE AT
EACH NETWORK PROTECTOR LOCATION. HOWEVER, SOLID STATE RELAYS ARE
TYPICALLY NOT AFFECTED BY VOLTAGE FLUCTUATION AND ARE WELL SUITED FOR
LABORATORY CALIBRATIONS.