Single-phase two-wire prepayment kWh meter, one meter with one IC card.upper counter display total energy used, down LED count Detailed description: 1. Summary 1.1 DDSY Type Single-Phase Electronic Prepaid Kilowatt Hour Meter (IC card type) is developed on basis of DDS Type Single-Phase Electronic Kilowatt Hour Meter, by adding a data processing controller. In the meter, ADE 7755 measurement chip ...