... :1, Controlled by AF. Automatically detect illumination,When the light is below 7Lux, only make a sound over 52dB±8dB ... After lasting 60s±20s , it will turn off automatically.2, Light-sensing device inside the switch can automatically detect illumination. When ... has special functions can use 3 wires, such as some emergency products.technical parameters:1,working voltage:175VAC~250VAC 50Hz2,power ...