System Sensor B324RL

These plug-in Sensor relay bases are for use with System Sensor 300 Series sensor heads (can also be used with obsolete 1151E/2151E sensors). They are designed to operate in both 2 and 4-wire systems, with screw terminals provided for power connections. Normally open and normally closed relay contacts are provided on a separate terminal block. The circuit built into the base provides current limiting to the sensor in the alarm state. The relay is controlled directly from the sensor, therefore as the sensor is latched in alarm, so will be the base. For the B324RL and B312RL latching relay bases, the alarm condition can only be terminated by removal of the supply to the sensor and base. The B312NL Non-latching base periodically isolates the sensor from the supply, hence providing an “automatic reset” once the alarm stimulus has cleared.