12.7.3
Rate-of-change frequency protection SAPFRC
M16256-2 v6
Prepare the IED for verification of settings as outlined in section
in this chapter.
12.7.3.1
Verifying the settings
M16256-8 v1
Verification of START value and time delay to operate
M16256-10 v5
1.
Check that the settings in the IED are appropriate, especially the START value and the
definite time delay. Set
StartFreqGrad, to a rather small negative value.
2.
Supply the IED with three-phase voltages at their rated values.
3.
Slowly decrease the frequency of the applied voltage, with an increasing rate-of-change
that finally exceeds the setting of
StartFreqGrad, 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.
Check 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.
Extended testing
M16256-29 v4
1.
The test above can be repeated to check a positive setting of
StartFreqGrad.
2.
The tests above can be repeated to check the time to reset.
3.
The tests above can be repeated to test the RESTORE signal, when the frequency
recovers from a low value.
12.7.3.2
Completing the test
M16256-39 v4
Continue to test another function or end the test by changing the
TestMode setting to Off.
Restore connections and settings to their original values, if they were changed for testing
purposes.
12.7.4
Frequency time accumulation protection function FTAQFVR
GUID-F7BD8E10-EF88-4698-87F4-0D4365004705 v2
Prepare the IED for verification of settings as outlined in section “Overview” and section
“Preparing for test” in this chapter.
12.7.4.1
Verifying the settings
GUID-864636E0-6399-44E1-BD2C-C2113FB78C61 v3
Time measurement and the injection of current and voltage can be done using a common test
equipment.
Verification of the
START
value and time delay to operation
1.
Connect the test set for the injection of three-phase currents and three-phase voltages to
the appropriate current and voltage terminals of the IED.
2.
Ensure that the settings in the IED are appropriate, especially the
CurrStartLevel,
FreqHighLimit, FreqLowLimit, UHighLimit and ULowLimit setting.
3.
Supply the IED with three-phase currents and voltages at their rated value.
4. Slowly decrease the frequency of the applied voltage until it crosses the frequency high
limit and the
START
signal appears.
5. Check that the
FREQOK
signal appears.
1MRK 502 067-UEN B
Section 12
Testing functionality by secondary injection
195
Commissioning manual
