4. Apply three-phase currents with their rated value and zero voltages.
5. Decrease the measured current in one phase until the DLD1PH signal appears.
6. This is the point at which the dead line condition is detected. Check the value of the
decreased current with the set value IDLDPU (IDLDPU is in percentage of the base
current IBase).
11.9.2.5 Checking the operation of the dv/dt and di/dt based function
Check the operation of the dv/dt and di/dt based function if included in the IED.
1. Simulate normal operating conditions with the three-phase currents in phase with
their corresponding phase voltages and with all of them equal to their rated values.
2. Change the voltages and currents in all three phases simultaneously.
The voltage change must be higher than the set value DVPU and the current change
must be lower than the set value DIPU.
• The BLKV and BLKZ signals appear without any time delay. The BLKZ
signal will be activated only if the internal deadline detection is not activated
at the same time.
• 3PH should appear after 5 seconds, if the remaining voltage levels are lower
than the set VDLDPU of the dead line detection function.
3. Apply normal conditions as in step
1.
The BLKV, BLKZ and 3PH signals should reset, if activated, see step 1 and 2.
4. Change the voltages and currents in all three phases simultaneously.
The voltage change must be higher than the set value DVPU and the current change
must be higher than the set value DIPU.
The BLKV, BLKZ and 3PH signals should not appear.
5. Repeat step
2.
6. Connect the nominal voltages in all three phases and feed a current below the trip
level in all three phases.
7. Keep the current constant. Disconnect the voltage in all three phases simultaneously.
The BLKV, BLKZ and 3PH signals should not appear.
8. Change the magnitude of the voltage and current for phase 1 to a value higher than
the set value DVPU and DIPU.
9. Check that the pickup output signals PU_DV_A and PU_DI_A and the general
pickup signals PU_DV or PU_DI are activated.
10. Check that the pickup output signals for the current and voltage phases 2 and 3 are
activated by changing the magnitude of the voltage and current for phases 2 and 3.
Section 11 1MRK 504 165-UUS -
Testing functionality by secondary injection
234 Transformer protection RET670 2.2 ANSI
Commissioning manual
To Next Page
Loading...
Need help?
General
