We used to have proximity switches on our wedge plug valves. They were activated while the valve was seated in either the open or closed positions by switch and shaft collar “contact”. During operation of the valves, once unseated, the valve indication on the TDC would go from either open or closed to moving. As for the Wilson Synder we’ve never had an in house proximity switch. Now that we use the MEA Operator it has a local switch for seat/unseat. I do not see any reason though why the shaft couldn’t be tapped for bolt installations that will “contact” proximity switches located at the Drum 1, Drum 2 and Bypass positions. As for showing seated/unseated some sort of collar “contacting” a proximity switch as we have with our MEA appears to be an easy installation. One thing to keep in mind is that the Coke Dust will sometimes keep the switches from working, so occasional cleaning of the switches may be needed.
