GE Multilin
N60 Network Stability and Synchrophasor Measurement System
1-19
1 GETTING STARTED
1.5 USING THE RELAY
1
1.5.7 COMMISSIONING
The N60 requires a minimum amount of maintenance when it is commissioned into service. Since the N60 is a micropro-
cessor-based relay, its characteristics do not change over time. As such, no further functional tests are required.
Furthermore, the N60 performs a number of continual self-tests and takes the necessary action in case of any major errors
(see the
Relay Self-tests
section in chapter 7 for details). However, it is recommended that N60 maintenance be scheduled
with other system maintenance. This maintenance may involve the in-service, out-of-service, or unscheduled maintenance.
In-service maintenance:
1.
Visual verification of the analog values integrity such as voltage and current (in comparison to other devices on the cor-
responding system).
2.
Visual verification of active alarms, relay display messages, and LED indications.
3.
LED test.
4.
Visual inspection for any damage, corrosion, dust, or loose wires.
5.
Event recorder file download with further events analysis.
Out-of-service maintenance:
1.
Check wiring connections for firmness.
2.
Analog values (currents, voltages, RTDs, analog inputs) injection test and metering accuracy verification. Calibrated
test equipment is required.
3.
Protection elements setting verification (analog values injection or visual verification of setting file entries against relay
settings schedule).
4.
Contact inputs and outputs verification. This test can be conducted by direct change of state forcing or as part of the
system functional testing.
5.
Visual inspection for any damage, corrosion, or dust.
6.
Event recorder file download with further events analysis.
7.
LED Test and pushbutton continuity check.
Unscheduled maintenance such as during a disturbance causing system interruption:
1.
View the event recorder and oscillography or fault report for correct operation of inputs, outputs, and elements.
If it is concluded that the relay or one of its modules is of concern, contact GE Multilin for prompt service.
