Trumpy on the PLC equipment I deal with, the Emergency stop button is hardwired to the MCR. We are not allowed to use an Estop in the PLC. We also use light curtains, step mats (shut the machine off if the operator steps into a hazard area), safety gates & cables (both interlocked into the Estop line). I don't think we will ever get them "idiot proof", the idiots just keep getting smarter!
