Alstom MiCOM P846, Техническое руководство

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P846/EN FD/D Firmware Design
(FD) 9-20
MiCOM P846
FD
The level of the field voltage
a from the opto-isolated inputs and the relay
data acquisition function every time it is executed. The
time and date from the board
attempt to log a maintenance record in battery
•
The battery status
•
•
The integrity of the digital signal I/O dat
contacts is checked by the
operation of the analog data acquisition system is continuously checked by the
acquisition function every time it is executed, by means of sampling the reference
voltages
•
The operation of the IRIG-B board is checked, where it is fitted, by the software that
reads the
In the unlikely event that one of the checks detects an error within the relay’s subsystems,
the platform software is notified and it will
backed-up SRAM. If the problem is with the battery status or the IRIG-B board, the relay will
continue in operation. However, for problems detected in any other area the relay will initiate
a shutdown and re-boot. This will result in a period of up to 5 seconds when the protection is
unavailable, but the complete restart of the relay including all initializations should clear most
problems that could occur. As described above, an integral part of the start-up procedure is
a thorough diagnostic self-check. If this detects the same problem that caused the relay to
restart, i.e. the restart has not cleared the problem, then the relay will take itself permanently
out of service. This is indicated by the ‘Healthy’ LED on the front of the relay, which will
extinguish, and the watchdog contact that will operate.