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G 2.2.4 -
H 2.2.4 -
J 2.2.5 • The harmonic restraint function changed to freeze the definite and IDMT timers.
• The maximum value of the settings IMin1, IMin2, IMin3 and IMin4 has been decreased
to 1000.0 % of IBase.
11.5.2.2 Verifying the settings
SEMOD56287-72 v10
The verification of the non-directional phase overcurrent function is done as instructed
below, but without applying any polarizing voltage.
1. Connect the test set for current injection to the appropriate IED phases.
If there is any configuration logic that is used to enable or block any of the four available
overcurrent steps, make sure that the step under test is enabled (for example, end fault protection).
If 1 out of 3 currents are chosen for operation: Connect the injection current to phases A and
neutral.
If 2 out of 3 currents are chosen for operation: Connect the injection current into phase A and out
from phase B.
If 3 out of 3 currents are chosen for operation: Connect the symmetrical three-phase injection
current into phases A, B and C.
2. Connect the test set for the appropriate three-phase voltage injection to the IED phases A, B and
C. The protection shall be fed with a symmetrical three-phase voltage.
3. Block higher set stages when testing lower set stages by following the procedure described below:
3.1. Set the injected polarizing voltage larger than the set minimum polarizing voltage (default is
5% of VBase) and set the injection current to lag the appropriate voltage by an angle of about
80° if forward directional function is selected.
If 1 out of 3 currents are chosen for operation: The voltage angle of phase A is the reference.
If 2 out of 3 currents are chosen for operation: The phase angle of the phase-to-phase
voltage AB is the reference for APhase.
If 3 out of 3 currents are chosen for operation: The voltage angle of phase A is the reference.
If reverse directional function is selected, set the injection current to lag the polarizing voltage
by an angle equal to 260° (equal to 80° + 180°).
3.2. Increase the injected current, note the trip value of the tested step of the function and
compare it to the set value.
3.3. Decrease the current slowly, note the reset value and compare it to the reset ratio 95%.
4. If the test has been performed by injection of current in phase A, repeat the test, injecting current
into phases B and C with polarizing voltage connected to phases B, respectively C (1 out of 3
currents for operation).
5. If the test has been performed by injection of current in phases AB, repeat the test, injecting current
into phases BC and CA with the appropriate phase angle of injected currents.
6. Connect a trip output contact to a timer.
7. Set the injected current to 200% of the trip level of the tested stage, switch on the current and
check the time delay.
For inverse time curves, check the trip time at a current equal to 110% of the trip current for txMin.
8. Check that all trip and pickup contacts trip according to the configuration (signal matrixes).
9. Reverse the direction of the injected current and check that the protection does not trip.
1MRK 504 165-UUS Rev. J Section 11
Testing functionality by secondary injection
Transformer protection RET670 169
Commissioning manual
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