Built as a definite purpose contactor

featuring a precise pick-up voltage range of 171-184V and a drop-out voltage of 55-90V

Direct Replacement: Replaces legacy part numbers 024-18785-000 and 024-18785A000 without requiring specialized wiring modifications

Common Questions Can the manual override switch be used to bypass a failed controller

System Sensor APA151 Annunciator Built as a definite purposeThe System Sensor APA151 is a critical remote annunciator with piezo alert designed for HVAC duct smoke detection systems. Engineered to meet NFPA 90A requirements, this accessory provides both audible and visual notification for 4 wire conventional duct smoke detectors when a system control panel is not present. Operating at 24 VDC (nominal range 16 to 33 VDC), the APA151 features a high visibility red alarm LED and a green power LED to ensure