PM861 processor going into fault mode repeatedly
we have two PM861 processors in hot standby configuration. But every once in a while both processors along with there communication interface modules go into fault mode. The fault led blinks red in the primary processor and in the redundant processor the fault led is solid red. Also dual led is glowing in the primary processor while it is off in the redundant processor. When both the processor are restarted and program is downloaded into them they work all ok. what could be the oproblem ?? plz suggest.