3 U
0
×
U
L1
U
L2
U
L3
+
+
=
IEC00000276 V1 EN-US
(Equation 111)
Where:
U
L1
, U
L2
and U
L3
IEC00000275 V1 EN-US
are the measured phase voltages
4.
Compare the result with the set value of the zero-sequence operating voltage (consider
that the set value
3U0> is in percentage of the base voltage.)
5.
Repeat steps
and
. Then slowly increase the measured current in one phase until the
BLKU signal disappears.
6.
Record the measured current and calculate the corresponding zero-sequence current
according to the equation (observe that the currents in the equation are phasors):
0
L1
L2
L3
3
=
I
I
I
I
×
+
+
IECEQUATION00019 V1 EN-US
(Equation 113)
Where:
1
2
3
L
L
L
I
I and I
,
IECEQUATION00020 V1 EN-US
are the measured phase currents
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.
12.9.2.4
Measuring the operate value for the dead line detection function
GUID-4ABF1FD4-F6D3-4109-AFE5-552875E558A0 v4
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).
12.9.2.5
Checking the operation of the du/dt and di/dt based function
M1405-96 v11
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
Section 12
1MRK 502 067-UEN B
Testing functionality by secondary injection
202
Commissioning manual