DDSY 169 single phase electronic prepaid KWH meter adopts the newest technique of personal computer and electronic currency IC card for purchasing electricity media. Such as electrical energy calculation, load control and users, information management. The product is an ideal produc t when reforming electric-use system,achieving electrical energy to commercialize,setting charge and adjusting load state in the electric-network. The product can be installed in the electric meter box, indoor,the ambient temperature is -25-+60 temperature.The relative humidity is not more than 85%.