The DDSY23S single-phase keypad prepayment energy meter is an energy metering instrument, which uses digit as data exchange medium. Switchable between prepaid and post-paid modes, the energy meter has various communication options which allow ease of AMI/AMR integration. Its design philosophy focuses on being humane, modular and global-oriented. It also features high measuring accuracy, flexible settlement in kWh or credit, multi tariffs and outstanding anti-tamper performance. DDSY23S meters have been found widely used in residential, commercial and industrial field.