Cutler-Hammer HWT-500, Инструкция по эксплуатации

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I.B. 35-557
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Time Delay Module Test (Optional)
Although the instantaneous overcurrent pickup point cannot be calibrated, the time delay function of
the module can be tested. Install the time delay module on the SSNPR. Make certain that the
network protector contacts are closed.
All the switch positions remain the same as used in the “Close Test” with the exception of the Phase
Switch that must be changed to the 180 position.
By rotating the VARIAC you can increase the reverse current value. This value should be quickly
increased to approximately twice the nominal trip setting. At this point begin the timing sequence and
end the timing sequence when the network protector breaker trips. The standard time setting is
variable from 20 to 200 seconds and is adjusted using the time potentiometer located on the time
delay module.
SSNPR Watt-Var Module Trip Test (Optional)
The test connections are the same as shown on page 33.
Switch Positions
Network protector closed and set for automatic operation.
TEST Switch – “RELAY” position
I & PV Switch – AI position
Supp VM Switch – CA position
PHASE switch – 180 position
VARIAC – zero position (not used in this test)
SUPPLY Switch – 216 or 480 position depending on network system voltage
NOTE – Make certain that the phasing adjustment of the SSNPR is in the –5 degrees range before
commencing the Close Test.
A pushbutton test switch is provided on this module to permit testing of the watt-var shift without the
need of an overcurrent condition. When this test switch is depressed the magnitude of reverse
current required to trip the protector will increase approximately four times its nominal 180-degree
value.
By rotating the VARIAC you can increase the reverse current value. The point at which the network
protector breaker trips should be approximately four times the nominal trip value at 180 degrees.
This increase in trip current proves that the watt-var function is performing properly.