Checking That The Binary Inputs And Outputs Operate As Expected; Measuring The Operate Value For The Negative Sequence Function - Hitachi RED670 Commissioning Manual

Section 11
Testing functionality by secondary injection
The verification is divided in two main parts. The first part is common to all fuse failure supervision
options, and checks that binary inputs and outputs operate as expected according to actual
configuration. In the second part the relevant set operate values are measured.
11.9.2.1

Checking that the binary inputs and outputs operate as expected

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.
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3. Disconnect the dc voltage from the DISCPOS binary input terminal.
4. Connect the nominal dc voltage to the MCBOP binary input.
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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.
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8. Establish normal voltage and current operating conditions simultaneously and observe the
corresponding output signals.
They should change to logical 0 as follows:
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11.9.2.2

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):
198
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.
The BLKUand BLKZ signals should appear without any time delay.
All undervoltage-dependent functions must be blocked.
There should be no change in the high status of the output signals BLKU and BLKZ.
The signal 3PH will appear.
Signal 3PH after about 25ms
Signal BLKU after about 50ms
Signal BLKZ after about 200ms
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1MRK 505 378-UEN Rev. K
Line differential protection RED670
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