The 785C product line consists of medium to large spring-return, single-acting and double-acting piston actuators that provide accurate, high thrust output for short to long stroke applications. These actuators are available for a wide range of medium to large size Fisher direct stroke control valves.
Single-acting actuators utilize an internal bias spring that forces the actuator piston rod to extend or retract upon loss of supply pressure, thus ensuring a fail-closed or fail-open mode of operation. This effectively eliminates the need for holding valves and tanks in most configurations.