ABB RELION RET670, Commissioning Manual, Page: 218 / 328

11.5.15.2 Completing the test
Continue to test another function or end the test by changing the TESTMODE setting to
Disabled . Restore connections and settings to their original values, if they were changed
for testing purposes.
11.6 Voltage protection
11.6.1 Two step undervoltage protection UV2PTUV (27)
Prepare the IED for verification of settings outlined in Section "Preparing the IED to
verify settings" .
11.6.1.1 Verifying the settings
Verification of pickup value and time delay to trip for Step 1
1. Check that the IED settings are appropriate, especially the PICKUP value, the
definite time delay and the
1 out of 3 operation mode.
2. Supply the IED with three-phase voltages at their rated values.
3. Slowly decrease the voltage in one of the phases, until the PICKUP signal appears.
4. Note the trip value and compare it with the set value.
The trip value in secondary volts is calculated according to the
following equations:
For phase-to-ground measurement:
sec
100
3
Vpickup VBase VT
VTprim
<
´ ´
ANSIEQUATION2430 V1 EN
(Equation 96)
For phase-to-phase measurement:
sec
100
Vpickup VT
VBase
VTprim
<
´ ´
ANSIEQUATION2431 V1 EN
(Equation 97)
5. Increase the measured voltage to rated load conditions.
6. Check that the PICKUP signal resets.
7. Instantaneously decrease the voltage in one phase to a value about 20% lower than
the measured trip value.
8. Measure the time delay for the TRIP signal, and compare it with the set value.
Section 11
1MRK 504 165-UUS -
Testing functionality by secondary injection
212 Transformer protection RET670 2.2 ANSI
Commissioning manual