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For such critical system, all commands should be through hard wired system; Id not recommend using Modbus or any other kind of communication to operate the valves around the coke drums.
Rotork is Ok for all actuators on isolation valves and switch valves, while using “release relay” to disable the main contactor. Thus any move from the motor cannot occur. When the drum switch is done, the operator “release” the valve. Then it will not move until the “release” switch is switched back to his position.
However, no matter what, the human factor will always be there, since everything should be handled from local panel. Even, the release relay could be activated/deactivated from local panel by a local bypass maintenance switch.