D
These Ethernet IOnet components (switch) fail and a diagnose alarm in DCS is received - "Input unhealthy on IO module IO net1 message time out & Output unhealthy on IO module IO net1 message time out"
Possible reasons - Internal temperature enclosure 53 deg C, lack of maintenance, power quality issue, redundancy questionable, RCA needed
Possible reasons - Internal temperature enclosure 53 deg C, lack of maintenance, power quality issue, redundancy questionable, RCA needed