The Spence Trip Stop Pilot is an ideal solution for preventing over-pressurization of the downstream system. Click this video to see how it works:

During normal operation, the Trip Stop Pilot is mechanically held open with a latch. Steam supply pressure is piped to the diaphragm of the trip stop main valve holding it in the open position. Reduced pressure is controlled by a pressure-reducing valve upstream. If the reduced pressure increases to the set pressure of the Trip Stop Pilot, two things happen:

• The weighted lever is unlatched, shutting off the steam supply to the trip stop main valve diaphragm chamber
• and the actuating pressure in the diaphragm chamber is vented downstream. Venting of the actuating pressure allows the spring to shut the main valve.

The Trip Stop Pilot must be manually reset after being tripped which can only be done when the steam pressure is less than the pilot’s set pressure. To learn more about Spence valves and to get proper sizing for your system, contact the team at Campbell-Sevey.