The Model RBVS is designed to monitor the fully open position of a ball valve installed in a sprinkler system. The unit will fi t on most ball valves installed on back-fl ow-preventers and alarm trim lines of dry, alarm, and deluge sprinkler valves. The switch operates if the ball valve handle is moved from the open position. However, the switch does not track the position of the handle or ball. When the ball valve handle is in the open position, a spring-loaded switch button will contact the valve handle. When the handle is moved from the open position, this switch button extends to the tripped position, and the RBVS contacts change state, thereby opening or closing a circuit. A cover tamper switch is available and is activated by the removal of the RBVS housing cover. If an attempt is made to remove the RBVS by the removal of the mounting brackets, the unit will be set into the tripped mode by this action.