Built-In Overcurrent Feature (Non-Directional); Overcurrent Feature With Current Restraint - ABB RET670 Installation And Commissioning Manual

Section 13
Verifying settings by secondary injection
13.9.1.1
13.9.1.2
168
quantity from the three-phase group, difference between maximum and minimum
quantities (unbalance) can be derived and then used in the function.
Due to the versatile possibilities of CVGAPC itself, but also the possibilities of
logic combinations in the application configuration of outputs from more than one
CVGAPC function block, it is hardly possible to define a fully covering general
commissioning test.

Built-in overcurrent feature (non-directional)

Procedure
1. Go to Main menu/Test/Function test modes/Multipurpose protection/
GeneralCurrentVoltage(GAPC)/GFx and make sure that CVGAPC to be
tested is unblocked and other functions that might disturb the evaluation of
the test are blocked.
2. Connect the test set for injection of three-phase currents to the appropriate
current terminals of the IED in the 670 series.
3. Inject current(s) in a way that relevant measured current (according to setting
parameter CurrentInput) is created from the test set. Increase the current(s)
until the low set stage operates and check against the set operate value.
4. Decrease the current slowly and check the reset value.
5. Block high set stage if the injection current will activate the high set stage
when testing the low set stage according to below.
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
1MRK 504 088-UEN C
Installation and commissioning manual