Measuring The Operate Value For The Negative Sequence Function - ABB rec670 Commissioning Manual

Section 10
Testing functionality by secondary injection
10.8.2.2
136
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. Connect the nominal dc voltage to the DISCPOS binary input.
• The signal BLKU should appear with almost no time delay.
• The signals BLKZ and 3PH should not appear on the IED.
• Only the distance protection function can operate.
• Undervoltage-dependent functions must not operate.
3. Disconnect the dc voltage from the DISCPOS binary input terminal.
4. Connect the nominal dc voltage to the MCBOP binary input.
• The BLKUand BLKZ signals should appear without any time delay.
• All undervoltage-dependent functions must be blocked.
5. Disconnect the dc voltage from the MCBOP binary input terminal.
6. Disconnect one of the phase voltages and observe the logical output signals on
the binary outputs of the IED.
BLKU and BLKZ signals should appear simultaneously wether the BLKU and
BLKZ reset depends on the setting SealIn "on" or "off". If "on" no reset, if "off"
reset.
7. After more than 5 seconds disconnect the remaining two-phase voltages and all
three currents.
• There should be no change in the high status of the output signals BLKU
and BLKZ.
• The signal 3PH will appear.
8. Establish normal voltage and current operating conditions simultaneously and
observe the corresponding output signals.
They should change to logical 0 as follows:
• Signal 3PH after about 25ms
• Signal BLKU after about 50ms
• Signal BLKZ after about 200ms

Measuring the operate value for the negative sequence function

Measure the operate value for the negative sequence 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. Slowly decrease the measured voltage in one phase until the BLKU signal
appears.
3. Record the measured voltage and calculate the corresponding negative-
sequence voltage according to the equation (observe that the voltages in the
equation are phasors):
1MRK 511 360-UEN A
Bay control REC670 2.1 IEC
Commissioning manual