Systemsensor D4240 Duct Smoke Detector


D4240 photoelectric duct smoke detectors are 4-wire detectors that feature pivoting housings that fit both square and rectangular footprints and mount to round or rectangular ductwork. They operate in airflow speeds of 100 to 4,000 fpm, in temperatures of –4 to 158 °F, and a humidity range of 0 to 95% (non-condensing). Their plug-in sensor heads offer improved false-alarm immunity and simple installation, testing, and maintenance. An improved cover design isolates the sensor head from the low-flow feature for simple maintenance. The InnovairFlex® housings provide ample wiring space, 3/4-inch conduit knockouts, and built-in short-circuit protection to prevent damage to sensitive components during installation.