The Shunt Controller allows two circuits to be temporally isolated from an active security system. The unit has two alarm inputs and each one is monitored by a 2K2 resistor. If this input is either open circuit or closed circuit the input is considered to be in alarm. Similarly the set input is also monitored by a 2K2 resistor. The set input controls the isolation of the other two inputs.
Four relays are provided for alarm annunciation and control. In addition a buzzer is provided for local feedback to users.
There are two modes of operation of the unit, timed and non timed, which are selected by using the on board switches. In both modes isolation of the two alarm inputs is initiated by applying the 2K2 resistor to the set input. In the non timed mode the isolation will remain until the set condition is removed (by either an open or closed circuit on the set input). In the timed mode the isolation will remain until the selected time matures or, optionally, until the set condition is removed as in the non timed mode.