Home › Forums › Coking › Safety › Safety Interlocks, Automation, Fire Suppression › Safety Interlocks › Proximity Switches for Manual Switch Valve and Drum Isolation Valves › RE: Proximity Switches for Manual Switch Valve and Drum Isolation Valves
We tried prox switches at our Coker, and had disappointing results. The service is too hot / severe to expect reliable operation from these devices. We have had much better luck using pressure indications located between the switch valve and drum isolation valves. The pressure indication is purged using 150 psig steam, and 150 psig purge steam is piped into the system there as well.