DDSU-104 series single-phase DIN-rail power meter is developed by our company by adopting microelectronics technology and imported large-scale integrated circuits, applying advanced digital sampling and processing technology and SMT technology. It is a new type of single-phase two-wire active energy meter with completely independent intellectual property rights. Its performance is in full compliance with the relevant technical requirements of GB / T17215.321-2008 (Level 1 and Level 2 static AC active energy meter), it can accurately and directly measure the active energy consumption of the loads in the 50Hz or 60Hz single-phase AC power grid, the meter displays the active power by the 8-bit LCD display, and it has RS485 communication function. The meter has the following features: good reliability, small size, light weight. Good reliability, small size, light weight, beautiful appearance, easy to install, etc.