Infrared diodes are placed in the special chamber.The chamber can shield external light, but don't affect the smoke into it

Wireless alarm devices with high reliability  based om Zigbee standard design,they can be used for smart home to detect smog density in the air and provide  an alarm.The detector is suitable for detect the smoke in house, shop, hotel, restaurant, office building, school, bank, library, computer house and storehouse etc.

Stand alone Smoke Detector Main Features

Hush functionAC power supply,9V back-up batteryTest button, HUSH buttonAccord with En14604 designInterconnects  40pcs detectorBattery low power indicationExecute criterion:EN14604;UL217

Standalone Smoke Detector Technical Parameter

Operating voltage,AC220V,with 9V back-up batteryTemperature Range,40°F to 100°F (4°C to 38°C)Humidity Range,5%-95% relative humidity (RH)Alarm output,Sound&flash alarmSensitivity,2.06%/ftSound level,85dB/3 meters (10ft)Interconnects,Up to 40pcs  smoke alarmHush function,YesDimension,Φ128*38mm

AC Powered Standalone Smoke Detector