AUMA AC 01.2 controller, paired with SA 07.2 actuator, receives simultaneous open/close command resulting in WRN NO REACTION warning

We have a multi-turn actuator that operates a 3" butterfly valve where we are experiencing intermittent issues where the valve will pause operation. This results in a fault in our system program due to excessive time for valve to open (> 120 sec) which shuts down the system. The valve actuator does not fault, but does occasionally shows a warning of WRN NO REACTION, which makes sense with the operation issue.
We have had a control company check out the data logging in the controller, and it shows repeated simultaneous open/close commands which result in the valve stopping. Command signals are coming from an Allen-Bradley PLC (Compact Logix L36ERM) through Allen-Bradley AC Output (1769-OA16) for the open/close command and Allen-Bradley AC Input (1769-IA16) for limit switch open/close. The program has been reviewed for discrepancies and there are no identified faults in the PLC components. We have replaced the Close command relay from the PLC and swapped out both of the Input/Output components of the PLC.
At this point, we cannot seem to identify where the simultaneous commands are originating, and as this is an intermittent issue, it is difficult to pinpoint a source.
 
It appears to be a very convoluted solution to send signals from a Compact Logix PLC through another PLC to drive a valve {if that is understood correctly}. On the assumption that the valve has to fully open or fully close {that is, not stop halfway}; then you appear to have a software fault despite being checked.

If you are not able to identify this intermittent fault. Then I would modify the software so that:
1. Once opening, the valve control ignores any further command until fully open.
2. Likewise, once closing, the valve control ignores any further command until fully closed.

Whilst working correctly, by monitoring the old control signals may assist in diagnosis.
 
Thanks for the input.

In our setup, there is only one PLC. I listed the respective output/input components of the whole PLC assembly. Sorry if that was confusing.

I believe our program is already set to perform similar to the manner you suggested. The program currently is set up to send the open command to the valve to remain open during the required portion of the routine. There is a timer that runs as a sub-routine for any valve operation through our system, where if the valve operation time is greater than 120 seconds, it throws a fault and shuts down the system.

We have not observed any indication of the errant open command at the main HMI panel through the PLC or the associated relays. The only place that the simultaneous commands are being found is in the data log for the actuator, and by visually observing the pausing/stopping of valve operation. I have checked the connections entering the controller, and all are tight and the wiring from the panel to the actuator seems to be in good condition. I am of the opinion that the issue lies in the actuator controller itself (possibly a bad board or other components).
 
It does have the ability to be operated by manual push buttons for open-close, but the switch on the controller must be moved from remote to local.
 
That I am unsure of. We have a controls contractor perform those types of diagnostic tests. I can say I have seen the valve act in this manner on several occasions, and there were no changes made to the switch. Unless there is some short in the switch, I don't see how that could cause this issue.
 
I discounted your valve controller electrics since it brings up it’s own warning.
If your actuator data log trends electrical signals then it should be easy enough to diagnose your ‘remote’ {PLC based} commands for conflicting actions.
Failing that, you are down to looking for a possible hardware fault; and operating the actuator by forcing the PLC o/p’s from your programmer.

If it is the actuator at at fault, I would be disappointed that your ‘controls contractor‘ had not diagnosed this before now.; PLC based systems are very easy to trace faults if the software allows.
 
It might be worth the effort to see exactly what the datalog logs or doesn't log. datalogs, Otherwise, you're working under assumptions, and we all know that how unproven assumptions can turn out. Is your 'controls contractor' stumped on this issue?
 
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