ABB RELION REL670, Руководство по установке и пусконаладке

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Frequency protection Chapter 11
Verifying settings by secondary
injection
3. Slowly decrease the magnitude of the applied voltage, until the
BLKDMAGN signal appears.
4. Note the voltage magnitude value and compare it with the set value,
IntBlkStVal
.
5. Slowly increase the frequency of the applied voltage, to a value
above StartFrequency.
6. Make sure that the START signal not appears.
7. Wait for a time corresponding to tTrip, and make sure that the TRIP
signal does not appears.
8.2.2 Completing the test
Continue to test another function or end the test by changing the test mode setting to off. Restore
connections and settings to their original values, if they were changed for testing purposes.
8.3 Rate-of-change frequency protection (PFRC, 81)
Prepare the terminal for verification of settings as outlined in section 1 "Overview" and section 2
"Preparing for test" in this chapter.
8.3.1 Verifying the settings
Verification of Start-value and time delay to operate
Procedure
1. Make sure that you have appropriate settings in the terminal, espe-
cially the Start-value and the definite time delay. Set StartFreqGrad,
to a rather small negative value.
2. Supply the terminal with three-phase voltages at their rated values.
3. Slowly decrease the frequency of the applied voltage, with an in-
creasing rate-of-change that finally exceeds the setting of Start-
FreqGrad
, and check that the START signal appears.
4. Note the operate value and compare it with the set value.
5. Increase the frequency to rated operating conditions, and zero
rate-of-change.
6. Make sure that the START signal resets.
7. Instantaneously decrease the frequency of the applied voltage to a
value about 20% lower than the nominal value.
8. Measure the time delay for the TRIP signal, and compare it with the
set value.