Kidde SD-SJ — SuperDuct four-wire duct smoke sensor with RJ-45 connectors, supplied as the sensor half only.The Kidde ordering table lists SD-SJ as Sensor (RJ45), separate from SD-CJ Controller (RJ45) and SD-4WJ Controller w/sensor, and a controller coupled with a compatible sensor is what makes up a four-wire duct smoke detector. The sensor samples duct air through a tube and signals the controller, which carries the relays that shut down fans and drive dampers. Photoelectric sensing with patented differential compensation; 0.67 to 2.46 %/ft obscuration Air velocity 100 to 4,000 ft/min Sensor assembly 8.70 in. × 5.45 in. × 1.90 in., under two inches deep Alarm, trouble, dirty and power LEDs; magnet-activated test switch Up to 100 ft of CMP harness between each sensor and its controller UL range -4 °F to 158 °F, ULC range -4 °F to 120 °F Exhaust tube included; sampling tube SD-T8 through SD-T120 ordered separately SD-SJ pairs only with the SD-CJ and SD-4WJ controllers. SD-ST is the same sensor with terminal blocks, and ESD-SJ and TSD-SJ belong to the ESD and TSD families.
