ELECTRONIC WATT-HOUR METER THAT HAVING PERCEIVING FUNCTION OF SURREPTITIOUS USE OF ELECTRICITY, ESPECIALLY A ZERO PHASE-SEQUENCE CURRENT TRANSFORMER

摘要

PURPOSE: An electronic watt-hour meter that having perceiving function of surreptitious use of electricity is provided to prevent power loss due to the surreptitious use of electricity of an electric power company or leakage. CONSTITUTION: An image current transformer(3) is installed on a low voltage power line(1) to detect a leakage current and is connected to a leakage current/surreptitious use of electricity detector of a signal detection unit(10). A current transformer(2) is connected to a current detector of the signal detection unit. The signal detection unit detects electric signals from the current transformer and the image current transformer. 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. A micro processor unit(40) controls a system with an embedded data communication program, and controls to display data by being connected to a display unit(50). 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.