Maintenance; General Maintenance; In-Service Maintenance; Out-Of-Service Maintenance - GE N60 Instruction Manual

N60 Network Stability and Synchrophasor
Measurement System
Chapter 9: Maintenance

Maintenance

This chapter outlines maintenance of the hardware and software.

9.1 General maintenance

The N60 requires minimal maintenance. As a microprocessor-based relay, its characteristics do not change over time.
While the N60 performs continual self-tests, it is recommended that maintenance be scheduled with other system
maintenance. This maintenance can involve in-service, out-of-service, or unscheduled maintenance.

9.1.1 In-service maintenance

1. Visual verification of the analog values integrity, such as voltage and current (in comparison to other devices on the
corresponding 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.

9.1.2 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.
N60 NETWORK STABILITY AND SYNCHROPHASOR MEASUREMENT SYSTEM – INSTRUCTION MANUAL 9-1