Areva MiCOM P225, Technical Manual

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Maintenance P225/EN CM/B11
MiCOM P225 Page 11/18
6.2 Equipment failures and solutions
6.2.1 COMM. ERROR
Communication module failure via RS485 port. This can be a hardware or software failure.
Action:
−
If communication is not being used, declare communication OFF in the
COMMUNICATION menu.
−
If communication is being used, remove the withdrawable part and return it to the
factory for repair.
6.2.2 CLOCK ERROR
This alarm appears if there are problems accessing the clock or there is an inconsistency in
the date being read.
Action:
If the alarm persists, remove the withdrawable part and return it to the factory for repair.
6.2.3 RAM ERROR
This alarm appears if the result of the checksum calculation in safeguarded RAM is incorrect.
The data in RAM will be considered inconsistent and will be lost.
This alarm may appear after downloading a new firmware version, after loss of the auxiliary
power supply while the relay was writing to safeguarded RAM or if there is a RAM hardware
fault.
Action:
Press button C on the relay front panel to clear the alarm.
If the alarm persists, de-energise then re-energise the relay.
If the alarm still persists, remove the withdrawable part and return it to the factory for repair.
As this is a minor alarm, it is possible to disable monitoring (which clears the alarm) by
setting "BATTERY ALARM" to NO (ALARM CONFIG. sub-menu.)
6.2.4 RTD/Therm ERROR
This alarm appears if:
−
The impedance measured at the relay detector input terminals is outside a certain
range. This may be due to short-wiring or an open circuit or a disconnected RTD.
−
The RTD monitoring board is faulty or wrongly fitted.
Action:
Check that the RTD's declared in the RTD sub-menu [49/38] or THERMISTOR sub-menu
[49] are correctly wired to the MiCOM relay.
Check the connection wiring for each RTD (short-wiring, open circuit).
After removing the withdrawable part, check that the RTD board is correctly connected to the
rest of the relay.
If the alarm persists, remove the withdrawable part and return it to the factory for repair.