Measuring The Trip Limit Of Set Values - ABB RET670 Commissioning Manual

Section 10
Testing functionality by secondary injection
Ensure that the maximum continuous current, supplied from the current source used for the test
of the IED, does not exceed four times the rated current value of the IED.
10.5.3.1

Measuring the trip limit of set values

1. Inject a phase current into the IED with an initial value below that of the setting.
2. Increase the injected current in the Ln or in the neutral (summated current input) phase until
the TRIP signal appears.
3. Disable the fault current
Observe to not exceed the maximum permitted overloading of the current circuits in the IED.
4. Compare the measured operating current with the set value.
10.5.3.2 Completing the test
Continue to test another function or end the test by changing the
Restore connections and settings to their original values, if they were changed for testing
purposes.
10.5.4 Four step residual overcurrent protection, (Zero sequence or
negative sequence directionality) EF4PTOC (51N/67N)
Prepare the IED for verification of settings as outlined in section
section "Preparing for test"
10.5.4.1 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
(default 5% of Vn) and set the injection current to lag the voltage by an angle equal to the set
reference characteristic angle (
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.
For inverse time curves, check the trip time at a current equal to 110% of the trip current for
txMin .
9. Check that all trip and pickup contacts trip according to the configuration (signal matrixes)
10. Reverse the direction of the injected current and check that the step does not trip.
140
in this chapter.
AngleRCA ), if the forward directional function is selected.
1MRK 504 154-UUS B
TestMode setting to Disabled .
"Requirements" and
Commissioning manual
SEMOD52967-11 v8
SEMOD52967-24 v5
SEMOD53296-3 v8
SEMOD53296-208 v6