4. Supply the IED with three-phase currents slightly more than the rated value.
5. Note the hot spot temperature (HPTMPMAX) and maintain it for another 1 hour.
6. Check the LOLINDAY and LOLINYRS outputs after 1 hour and compare it with the calculated loss
of life value using IEC standard method.
11.14.6.2 Completing the test
GUID-46EC57EA-375B-4DBD-BE18-914156083384 v1
Continue to test another function or end the test by changing the Test mode setting to Disabled. Restore
connections and settings to their original values, if they were changed for testing purposes.
11.14.7 Through fault monitoring PTRSTHR (51TF)
GUID-7AE60CB5-3CD5-4FE2-8D54-664AA78DD2DE v1
GUID-079BCF22-469C-42EA-B857-E28154EC13D9 v1
Prepare the IED for verification of settings outlined in Section
"Preparing the IED to verify settings".
11.14.7.1 Verifying the signals and settings
GUID-0295EF7C-217E-4400-B7C2-68C00A38ADF3 v1
The voltage or current can be injected using a common test equipment.
Verifying the through fault detection
GUID-148CA255-735B-42B3-9046-AD91B20DB261 v1
1. Supply the IED with three-phase current at rated value.
2. Ensure that the relevant settings for through fault detection such as W1 I pickup, W2 I pickup and
W3 I pickup are set correctly.
3. Ensure that the BLOCK and INHIBIT inputs are not activated.
4. Set t_MinTripDelay as 0 s to check the pickup level of through fault detection.
5. Slowly increase any phase current of any winding until ALARM signal appears.
6. Compare the injected phase current value with the set threshold limit value.
7. Bring the injected three-phase currents at the rated value.
8. Change the t_MinTripDelay setting to a particular value.
9. Slowly increase any phase current of any winding to the threshold limit and wait until the ALARM
signal appears.
10. Compare the wait time with the set t_MinTripDelay value.
11. Bring the injected three-phase currents to the rated value.
Verifying the fault I
2
t and cumulative I
2
t alarms
GUID-D7BF8A0C-17CC-49E3-B101-AB719D0822CC v1
1. Supply the IED with three-phase current at rated value.
2.
Ensure that the relevant settings for fault I
2
t alarm such as MaxI2tW1, MaxI2tW2 and MaxI2tW3 are
set correctly.
3. Ensure that the BLOCK and INHIBIT inputs are not activated.
4. Slowly increase any phase current of any winding until ALARM signal appears.
5. Continue to inject the same level of current until the I2TALM signal appears.
6. Compute the time between the ALARM signal raise to I2TALM signal raise and multiply with the
squared injected current.
7. Compare the calculated value with the set MaxI2tWx value.
8. Bring the injected three-phase currents to the rated value.
9.
Ensure that the relevant settings for fault cumulative I
2
t alarm such as MaxI2tCmlW1,
MaxI2tCmlW2 and MaxI2tCmlW3 are set correctly.
10. Slowly increase any phase current of any winding to the threshold limit and wait until the ALARM
signal appears.
11. Continue to inject the same level of current until the CMLI2TALM signal appears.
Section 11 1MRK 504 165-UUS Rev. J
Testing functionality by secondary injection
282 Transformer protection RET670
Commissioning manual
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