The Globe Model RCW Water Control Valve is a hydraulically operated external resetting differential latching style valve designed for use where quick-opening and total flooding of sprinkler system piping is desired. It is used as an automatic water control valve in Deluge, Dry Pipe, or Preaction systems, as well as foam-water sprinkler systems.
Setting of the Model RCW Valve requires water pressure in the diaphragm chamber provided via a connection from the main water supply from a point upstream of the system main control valve, through a restricted orifice.
Water pressure on the diaphragm is transferred to the plunger rod which forces the roller arm mechanism against the clapper, preventing the supply water from entering the sprinkler system piping. Actuation (tripping) of the Model RCW Valve is accomplished by releasing water from downstream of the restricted orifice. Water pressure release can be caused by a variety of types of actuation trim and devices. For example the supply can be fed to a line of wet pilot sprinklers for wet pilot type Deluge or Preaction systems. Other devices which can be used for valve actuation include a dry pilot actuator, or an electric solenoid valve with an associated releasing control panel.
Instructional videos can be found here under the 'installation' category.