Abstract: A valve comprising a housing defining an interior chamber; an inlet port; an outlet port; an exhaust port; an actuator that selectively allows and prevents communication between the inlet port and outlet port; and a bleed port providing communication between the inlet port and the interior chamber regardless of the position of the actuator. The housing may be surrounded by an environment that is exposed to combustibles and therefore classified as a hazardous environment. Even so, the valve may be rated for use in that environment even though the actuator may require more energy to operate than would normally be acceptable in that environment.

Abstract: A fieldbus valve station with a valve manifold and a communications module having a bus communication unit mounted therein for using a fieldbus protocol and connectable to a fieldbus network and to provide local and peer to peer network control by the valve station if a fault is detected or there is a break from the main fieldbus network.