Two, <R> and <S>, controllers of MKV system failed simultaneously at base load. At SOE first alarm was low hydraulic oil pressure, all standby and DC motors started.Trend showed 2/3 TTXD's were down for 1 minute. No additional process alarms prior to the trip. In diagnostic alarms only "power supply P15 out of limits" from <S> controller constantly coming&going. Strangely, no messages about controllers being rebooted or communication being lost.
Controllers statuses, DIAGC statuses and power supply voltages, hydraulic oil system operation were checked and found OK.
What can be a possible reasons for this kind of failure?
Thanks All for thinking.
Controllers statuses, DIAGC statuses and power supply voltages, hydraulic oil system operation were checked and found OK.
What can be a possible reasons for this kind of failure?
Thanks All for thinking.