Cutler-Hammer HWT-500, Инструкция по эксплуатации

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I.B. 35-557
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SSNPR Close Test
By rotating the VARIAC you can increase the overvoltage phasing value to the desired value at which
the SSNPR close contact makes and the breaker contacts close. The value at which the protector
closes is the reclose setting of the SSNPR. If it is necessary to increase or decrease this value by
less than (+/-) 20% for models 10 and 20SSNPR or (+/-) 40% for model 30 and 40 SSNPR, then the
following steps are necessary:
A. Set the reclose voltage adjust on the SSNPR to maximum (clockwise).
B. Apply the desired overvoltage phasing value across the open network protector.
C. While depressing the phase detector bypass switch, on the relay, slowly turn the reclose voltage
adjust counterclockwise until the protector closes.
D. The SSNPR should now be calibrated for the new overvoltage close setting. Reapply the new
overvoltage close value and verify that the breaker does close its contacts at the predetermined
setting.
SSNPR Trip Test
All of the switch positions remain the same as used in the “Close Test” with the exception of the
Phase switch which must be changed to the 180 position. The network protector breaker must be
closed and the I & PV switch must be changed to AI position.
By rotating the VARIAC you can increase the reverse current value to the desired value at which the
network protector contacts open. This value becomes the trip current setting of the SSNPR. If this
value is not correct and you wish to change the reverse trip setting, the following steps are necessary:
A. Set the trip current adjust on the SSNPR to maximum (clockwise).
B. Apply the desired reverse current through the closed network protector.
C. Slowly turn the trip adjust counterclockwise until the network protector trips.
D. The SSNPR should now be calibrated for the new current setting. Reapply the reverse current
and reaffirm the new trip setting.
Phase Detection Test
All of the switch positions remain the same as used in the “Close Test”. The SSNPR phase angle
adjust setting must be set to the +5 degrees (maximum clockwise) position.
Apply a zero degree (in phase) overvoltage close value that is much higher than the previously
calibrated value. Note that the network protector does not close. Depress the phase detector bypass
switch, on the relay, and note that the network protector does close. This test verifies the correct
functioning of the phase detector.
Restore the phase angle adjust to the original setting.