13 Maintenance
PCS-978 Transformer Relay
13-1
Date: 2012-10-09
NR numerical relay PCS-978 is designed to require no special maintenance. All measurement and
signal processing circuit are fully solid state. All input modules are also fully solid state. The output
relays are hermetically sealed.
Since the device is almost completely self-monitored, from the measuring inputs to the output
relays, hardware and software defects are automatically detected and reported. The
self-monitoring ensures the high availability of the device and generally allows for a corrective
rather than preventive maintenance strategy. Therefore, maintenance checks in short intervals are
not required.
Operation of the device is automatically blocked when a hardware failure is detected. If a problem
is detected in the external measuring circuits, the device normally only provides alarm messages.
13.1 Appearance Check
The relay case should be clean without any dust stratification. Case cover should be sealed well.
No component has any mechanical damage and distortion, and they should be firmly fixed in the
case. Relay terminals should be in good condition. The keys on the front panel with very good
feeling can be operated flexibly.
It is only allowed to plug or withdraw relay board when the supply is reliably switched off. Never
allow the CT secondary circuit connected to this equipment to be opened while the primary system
is live when withdrawing an AC module. Never try to insert or withdraw the relay board when it is
unnecessary.
Check weld spots on PCB whether they are well soldered without any rosin joint. All dual inline
components must be well plugged.
13.2 Failure Tracing and Repair
Failures will be detected by automatic supervision or regular testing.
When a failure is detected by supervision, a remote alarm is issued and the failure is indicated on
the front panel with LED indicators and LCD display. It is also recorded in the event record.
Failures detected by supervision are traced by checking the “
Superv Events
” screen on the LCD.
When a failure is detected during regular testing, confirm the following:
Test circuit connections are correct
Modules are securely inserted in position
Correct power supply voltage is applied
Correct analog inputs are applied
Test procedures comply with those stated in the manual
13.3 Replace Failed Modules
If the failure is identified to be in the relay module and the user has spare modules, the user can
Summary of Contents for PCS-978
Page 1: ...PCS 978 Transformer Relay Instruction Manual NR Electric Co Ltd ...
Page 2: ......
Page 6: ...Preface PCS 978 Transformer Relay IV Date 2013 01 16 ...
Page 10: ...Preface PCS 978 Transformer Relay VIII Date 2013 01 16 ...
Page 62: ...3 Operation Theory PCS 978 Transformer Relay 3 p Date 2013 01 16 ...
Page 250: ...4 Supervision PCS 978 Transformer Relay 4 b Date 2013 01 16 ...
Page 264: ...4 Supervision PCS 978 Transformer Relay 4 14 Date 2013 01 16 ...
Page 266: ...5 Management PCS 978 Transformer Relay 5 b Date 2013 01 16 ...
Page 272: ...5 Management PCS 978 Transformer Relay 5 6 Date 2013 01 16 ...
Page 334: ...6 Hardware Description PCS 978 Transformer Relay 6 60 Date 2013 01 16 ...
Page 370: ...8 Human Machine Interface PCS 978 Transformer Relay 8 d Date 2013 01 16 ...
Page 404: ...8 Human Machine Interface PCS 978 Transformer Relay 8 34 Date 2013 01 16 ...
Page 406: ...9 Configurable Function PCS 978 Transformer Relay 9 b Date 2013 01 16 ...
Page 446: ...10 Communication PCS 978 Transformer Relay 10 26 Date 2013 01 16 ...
Page 448: ...11 Installation PCS 978 Transformer Relay 11 b Date 2012 10 09 ...
Page 456: ...11 Installation PCS 978 Transformer Relay 11 8 Date 2012 10 09 ...
Page 458: ...12 Commissioning PCS 978 Transformer Relay 12 b Date 2012 12 07 ...
Page 468: ...12 Commissioning PCS 978 Transformer Relay 12 10 Date 2012 12 07 ...
Page 470: ...13 Maintenance PCS 978 Transformer Relay 13 b Date 2012 10 09 ...
Page 474: ...13 Maintenance PCS 978 Transformer Relay 13 4 Date 2012 10 09 ...
Page 476: ...14 Decommissioning and Disposal PCS 978 Transformer Relay 14 b Date 2012 10 09 ...
Page 478: ...14 Decommissioning and Disposal PCS 978 Transformer Relay 14 2 Date 2012 10 09 ...
Page 480: ...15 Manual Version History PCS 978 Transformer Relay 15 2 Date 2013 01 16 ...