Completing The Test; Restricted Earth Fault Protection, Low Impedance Refpdif; Verifying The Settings - ABB RET670 Commissioning Manual

1MRK 504 165-UEN A
11.3.2.2
11.3.3
11.3.3.1
Transformer protection RET670 2.2 IEC
Commissioning manual
Testing functionality by secondary injection
value. Normally a slightly higher operating value is no
problem as the sensitivity is not influenced much.
2. Increase the voltage and make note of the operate value U>Trip. This is done
by manual testing and without trip of the test set.
3. Connect the trip contact to the test set to stop the test set for measurement of
trip times below.
4. Reduce the voltage slowly and make note of the reset value. The reset value
must be high for this function.
5. Check the operating time by injecting a voltage corresponding to 1.2 ˣ
U>Trip level. Make note of the measured trip time.
6. If required, verify the trip time at another voltage. Normally 2 ˣ U>Trip is
selected.
7. If used, measure the alarm level operating value. Increase the voltage and
make note of the operate value U>Alarm. This is done with manual test and
without trip of the test set.
8. Measure the operating time on the alarm output by connecting the stop of the
test set to an output from tAlarm. Inject a voltage 1.2 ˣ U>Alarm and measure
the alarm time.
9. Check that trip and alarm outputs operate according to the configuration
logic.
10. Finally check that start and alarm information is stored in the event menu and
if a serial connection to the SA is available verify that the correct and only the
required signals are presented on the local HMI and on the SCADA system.
Information on how to use the event menu is found in the operator's
manual.

Completing the test

Continue to test another function or end the test by changing the TESTMODE
setting to Off. Restore connections and settings to their original values, if they were
changed for testing purposes.

Restricted earth fault protection, low impedance REFPDIF

Prepare the IED for verification of settings outlined in Section
to verify settings".

Verifying the settings

Section 11
SEMOD55257-73 v4
SEMOD55252-82 v8
"Preparing the IED
SEMOD55252-86 v11
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