I saw it occur today with a ControlLogix. It seems to occur when someone compiles/accepts edits. It takes about 10 seconds for OPC writing to function again. The scary part is that if you are holding a jog and then someone compiles/accepts edits, the bit is just stuck on ‘1’ until the OPC can write again, and then you have to poke the button again to get the ‘0’ to write on release!
Has this always been the case or is this new? Is there any mitigation?