Overcurrent Feature With Current Restraint; Overcurrent Feature With Voltage Restraint - ABB RET670 Commissioning Manual

1MRK 504 165-UEN A
11.8.1.2
11.8.1.3
Transformer protection RET670 2.2 IEC
Commissioning manual
Testing functionality by secondary injection
6. Connect a TRIP output contact to the timer.
7. Set the current to 200% of the operate value of low set stage, switch on the
current and check the time delay.
For inverse time curves, check the operate time at a current equal to 110% of
the operate current at tMin.
8. Check that TRIP and START contacts operate according to the configuration
logic.
9. Release the blocking of the high set stage and check the operate and reset
value and the time delay for the high set stage in the same way as for the low
set stage.
10. Finally check that START and TRIP information is stored in the event menu.
Information on how to use the event menu is found in the
operator's manual.

Overcurrent feature with current restraint

The current restraining value has also to be measured or calculated and the
influence on the operation has to be calculated when the testing of the operate
value is done.
Procedure
1. Operate value measurement
The current restraining value has also to be measured or calculated and the
influence on the operation has to be calculated when the testing of the operate
value is done.

Overcurrent feature with voltage restraint

Procedure
1. Connect the test set for injection of three-phase currents and three-phase
voltages to the appropriate current and voltage terminals of the IED.
2. Inject current(s) and voltage(s) in a way that relevant measured (according to
setting parameter CurrentInput and VoltageInput) currents and voltages are
created from the test set.
Overall check in principal as above (non-directional overcurrent feature)
3. Operate value measurement
The relevant voltage restraining value (according to setting parameter
VoltageInput) has also to be injected from the test set and the influence on the
operate value has to be calculated when testing of the operate value is done.
4. Operate time measurement
Definite times may be tested as above (non-directional overcurrent feature).
For inverse time characteristics the START value (to which the overcurrent
Section 11
SEMOD56488-35 v3
SEMOD56488-44 v5
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