ABB REG650 Commissioning Manual page 123

1MRK 502 049-UEN A
Commissioning manual
Commissioning and maintenance of the fault clearing system
All necessary operations such as opening of trip circuits, short-circuiting of current
circuits and opening of voltage circuits are automatically performed in the right order
to allow for simple and safe secondary testing even with the object in service.
Preparation
Before starting maintenance testing, the test engineers should scrutinize applicable
circuit diagrams and have the following documentation available:
• Test instructions for protection IEDs to be tested
• Test records from previous commissioning and maintenance tests
• List of valid settings
• Blank test records to fill in measured values
Recording
It is of utmost importance to carefully record the test results. Special test sheets
covering the frequency of test, date of test and achieved test values should be used.
IED setting list and protocols from previous tests should be available and all results
should be compared for differences. At component failures, spare equipment is used
and set to the requested value. A note of the exchange is made and the new measured
values are recorded. Test records for several years of testing should be stored in a
common file for a station, or a part of a station, to give a simple overview of the period
of testing and achieved test values. These test records are valuable when analysis of
service disturbances shall be done.
Secondary injection
The periodic maintenance test is done by secondary injection from a portable test set.
Each protection shall be tested according to the secondary injection test information
for the specific protection IED. Only the setting values adopted shall be checked for
each protection function. If the discrepancy between obtained value and requested set
value is too big the setting should be adjusted, the new value recorded and a note
should be made in the test record.
Alarm test
When inserting the test handle the alarm and event signalling is normally blocked.
This is done in the IED by setting the event reporting to Off during the test. This can
be done when the test handle is inserted or the IED is set to test mode from the local
HMI. At the end of the secondary injection test it should be checked that the event and
alarm signalling is correct by activating the events and performing some selected tests.
Self supervision check
Once secondary testing has been completed, it should be checked that no self-
supervision signals are activated continuously or sporadically. Especially check the
time synchronization system, GPS or other, and communication signals, both station
communication and remote communication.
Trip circuit check
When the protection IED undergoes an operational check, a tripping pulse is normally
obtained on one or more of the output contacts and preferably on the test switch. The
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