Conventional fire alarm smoke detector smoke probe sensor This device is photoeletronic detector uses a state-of-the-art optical sensing chamber. This smoke detector is compatible with all conventional fire alarm control panel Dual leds, two leds blink standby, provide 360dgree visibility With unique optical sensing chamber, engineered to sense smoke by a wide range of combustion sources. Unpolarized wire input to prevent the likelihood of wiring errors Specifications Operating voltage range: 9 to 28vdc volts non-polarized Standby current: 60µa @ 24 vdc Maximum alarm current (led on: ) 30ma @ 24 vdc Operating humidity range: 10% to 93% relative humidity, non-condensing Operating temperature range: 14°f to 122°f (-10°c to50°c) Adjustable sensitivity: 0.15ï½?0.3db/m Height: 2.2ë� (55 mm) installed in base Diameter: 4.0ë� (103 mm) Weight: 5.5 oz. (155 g)