Measuring The Operate Value For The Dead Line Detection Function; Checking The Operation Of The Du/Dt And Di/Dt Based Function - ABB RET650 2.1 IEC Commissioning Manual

1MRK 504 160-UEN -
10.6.1.4
10.6.1.5
Transformer protection RET650 2.1 IEC
Commissioning manual
Testing functionality by secondary injection
× + +
3 I = I I
0 L1 L2
IECEQUATION00019 V1 EN
Where:
,
I I and I
L 1 L 2 L 3
IECEQUATION00020 V1 EN
7. Compare the result with the set value of the zero-sequence operate current.
Consider that the set value 3I0< is in percentage of the base current IBase.

Measuring the operate value for the dead line detection function

1. Apply three-phase voltages with their rated value and zero currents.
2. Decrease the measured voltage in one phase until the DLD1PH signal appears.
3. This is the point at which the dead line condition is detected. Check the value of
the decreased voltage with the set value UDLD< (UDLD< is in percentage of the
base voltage UBase).
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 IDLD< (IDLD< is in percentage of the
base current IBase).

Checking the operation of the du/dt and di/dt based function

Check the operation of the du/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 DU> and the current
change must be lower than the set value DI<.
• The BLKU 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 UDLD< of the dead line detection function.
3. Apply normal conditions as in step 1.
The BLKU, BLKZ and 3PH signals should reset, if activated, see step
4. Change the voltages and currents in all three phases simultaneously.
The voltage change must be higher than the set value DU> and the current
change must be higher than the set value DI<.
I
L3
are the measured phase currents
Section 10
(Equation 4)
1 and 2.
87