Replacing Failed Relay; Lcd Message And Alarm Location - Toshiba GRE110 Instruction Manual

Message
ALM: CT
ALM: TC
ALM: CB
ALM: TP COUNT
ALM: OP TIME
ALM: ΣIY
( ): Probable failure location in the relay unit including its peripheral circuits.
If no message is shown on the LCD, this means that the failure location is either in the power supply
circuit or in the microprocessors. If the "Relay Fail" LED is off, the failure is in the power supply
circuit. If the LED is lit, the failure is in the microprocessors.
If a failure is detected by automatic supervision or regular testing, replace the failed relay unit.
Note: When a failure or an abnormality is detected during the regular test, confirm the following
first:
- Test circuit connections are correct.
- Correct power voltage is applied.
- Correct AC inputs are applied.
- Test procedures comply with those stated in the manual.

6.7.3 Replacing Failed Relay

If the failure is identified to be in the relay and the user has a spare relay, the user can recover the
protection by replacing the failed relay.
Repair at the site should be limited to relay replacement. Maintenance at the component level is not
recommended.
Check that the replacement relay has an identical Model Number and relay version (software type
form) as the removed relay.
The Model Number is indicated on the front of the relay. For the relay version, see Section 4.2.5.1.
Replacing the relay
CAUTION
The procedure of relay disinstallation and installation is as follows:
• Switch off the power supply.
WARNIN
• Remove the terminal blocks of relay leaving the wiring.
• To remove the relay unit from the panel, the screws of attachments are removed.
• Insert the (spare) relay unit in the reverse procedure.
Table 6.7.2 LCD Message and Alarm Location
Relay Unit
×(AC input circuit)(1)
×(Trip circuit)(1)
×(Circuit breaker)(1)
×(Trip count)(1)
× (Operation time)
× (Trip current)
After replacing the relay unit, check the settings including the data related to the
PLC, IEC103 and IEC61850, etc. are restored the original settings.
Hazardous voltage may remain in the DC circuit just after switching off the
power supply. It takes about 30 seconds for the voltage to discharge.
 175 
Failure location
AC cable CB or Cable
×
(2)
6 F 2 T 0 1 7 2
×
(2)
×
(2)
×
(2)
×
(2)
×
(2)