High Integrity AC 800 Redundunt Controllers Simultaneous failure
We have 800xA DCS with AC 800 M Controller with a dedicated High Integrity Redundant PM 865 Controllers with safty processors to manage our Emergency Shutdown System (ESD). We had a twice failure in both Primary and secondary controllers which lead to complete plant shutdown without indication along with loosing of the application for both controllers which require a downloading for the application through the connectivity server. Please advice noting that no power interruption noticed before failure.
As per my knowlodge, As your are facing problem with both controllers, it might be the external cause.
Can you please check the below mentioned as primary checks,
1 ) Check the Power supply hardware Circuit ( MCBs, DOR,PSs, Any loose connections in Terminal Blocks etc.,).
2) Check Battey Connections to the Controllers.
3) Any human errors.
4) what type of events you got in the HMI at the time of cotroller stoppage.
5) Is there any SA & SB power failure alarms in the system.
This may help you to find out the reasons.
we have same problem that our ESD sytem goes in failur state when we dignose we find that problem was with SM811 whenever our SM811 goes on Dignostic test during running system then it create problem and both controller goes on fault.
what we do to make it normal we give the sync pluse to the SM811 by external Push and download the controller and then system work fine but this happens many time.
we contact suppportline they give multiple solution but nothing work.now they told us that in Version 5.0 Rev E they solve this problem i don't know that Rev E with HI is released or not.
Which version you are using ?
Source: ESD Failure