Completing The Test; Four Step Residual Overcurrent Protection, (Zero Sequence Or Negative Sequence Directionality) Ef4Ptoc (51N/67N); Four Step Directional Ground Fault Protection - ABB RET670 Commissioning Manual

1MRK 504 165-UUS -
11.5.3.2
11.5.4
11.5.4.1
Transformer protection RET670 2.2 ANSI
Commissioning manual

Completing the test

Continue to test another function or end the test by changing the TESTMODE setting to
Disabled. Restore connections and settings to their original values, if they were changed
for testing purposes.
Four step residual overcurrent protection, (Zero sequence or
negative sequence directionality) EF4PTOC (51N/67N)
Prepare the IED for verification of settings outlined in Section
verify settings".
Values of the logical signals for D2PTOC are available on the local HMI under Main
menu/Tests/Function status/Current protection/
ResidualOverCurr4Step(51N_67N,4(IN>))/EF4PTOC(51N_67N;4(IN>)):x, where
x = instance number.
The Signal Monitoring in PCM600 shows the same signals that are available on the local
HMI.

Four step directional ground fault protection

1. Connect the test set for single current injection to the appropriate IED terminals.
Connect the injection current to terminals A and neutral.
2. Set the injected polarizing voltage slightly larger than the set minimum polarizing
voltage (5% of Vn) and set the injection current to lag the voltage by an angle equal
to the set reference characteristic angle (AngleRCA), if the forward directional
function is selected.
If reverse directional function is selected, set the injection current to lag the
polarizing voltage by an angle equal to RCA+ 180°.
3. Increase the injected current and note the value at which the studied step of the
function trips.
4. Decrease the current slowly and note the reset value.
5. If the test has been performed by injection of current in phase A, repeat the test,
injecting current into terminals B and C with a polarizing voltage connected to
terminals B, respectively C.
6. Block lower set steps when testing higher set steps according to the instructions that
follow.
7. Connect a trip output contact to a timer.
8. Set the injected current to 200% of the trip level of the tested step, switch on the
current and check the time delay.
Testing functionality by secondary injection
Section 11
"Preparing the IED to
181