Series RYH PIR sensor switches are a king of ful-automatic energy conservation switch can control the automatic connection and tim-delay closed of the switch with the themal energy of sending out by human body,When human body enters of leaves the measuring range or moves in the range,the switch will get through the circuit automatically,If the switch cannot measure the signal of moving human body,it will switch off the circuit after automatically time-delayed.The switch belongs to intelligent energy conservatin switch.