APC SM-501-P Photoelectric Duct Smoke Detector

The SM-501-P Photoelectric Duct Smoke Detector  The SM-501-P Photoelectric Duct Smoke Detector provides early detection of smoke and products of combustion present in air moving through HVAC ducts in Commercial, Industrial, and Residential applications. The unit is designed to prevent the re-circulation or spread of smoke by air handling systems, fans, and blowers. Complete systems may be shut down in the event of smoke detection. The SM-501-P  will operate on any one of four input voltages (230VAC, 115VAC, 24VAC, or 24VDC). The SM-501-P allows up to 30 detectors to be interconnected for many common functions.