POWER METER COMPRISING ELECTRONIC AND MECHANICAL DISPLAY UNIT, ESPECIALLY INCLUDING POWER LINE COMMUNICATION MODEM AND MECHANICAL DIGIT DISPLAY FOR POWER FAILURE

摘要

PURPOSE: A power meter comprising an electronic and mechanical display unit is provided, which checks power metering data using a mechanical digit display when power failure occurs a voltage is not supplied. CONSTITUTION: A current transformer(2) is installed on a low voltage power line(1) and is connected to a current detector of a signal detection unit(10). The signal detection unit detects signals from the current transformer and the low voltage power line. A controller(20) includes an A/D conversion unit converting signals from the signal detection unit into digital signals, and a calculation and memory unit calculating and storing converted data, and a serial communication interface exchanging data with a microprocessor unit(40). The micro processor unit controls a system with an embedded data communication program, and controls to display data by being connected to a display unit(50) and a mechanical digit display(60). The display unit displays data to the external. And a power line communication modem unit(30) transmits and receives a transmission command and the stored data through the low voltage power line by power line communication.