Energy meter for measuring residual current

Abstract

The invention provides an electric energy meter capable of measuring residual currents. The electric energy meter comprises a shell, a wiring terminal base, a phase line, a null line, a relay, a phase line current sampling resistor, a residual current transformer and a circuit device. The relay, the phase line current sampling resistor and the residual current mutual inductor are all arranged in the shell. The phase line and the null line penetrate through the residual current mutual inductor. The circuit device comprises a voltage sampling module, a signal processing module, an A / D conversion module, an electric energy metering module, a single-chip microcomputer processing module, a relay control module, a communication module, an LCD display module, a button module and a power module. The electric energy meter can measure and record the residual currents in user lines in real time and has the functions of residual current over-limit warning and event recording. The electric energy meter only needs to be improved on the basis of an existing intelligent electric energy meter, is not high in improvement cost, does not affect the functions and the overall dimension of the existing electric energy meter and is convenient to popularize in large scale.

Description

technical field [0001] The invention relates to an intelligent electric energy meter, in particular to an electric energy meter capable of measuring residual current. Background technique [0002] Residual current refers to the current in which the vector sum of the current vectors of each phase in the distribution line is not zero. In most cases, it is caused by the leakage of equipment or lines. When the leakage is serious, it will burn the electrical equipment or lines and cause a fire. Therefore, it is an effective protective measure to prevent personal electric shock, electrical fire and electrical equipment damage by residual current detection and installation of residual current operating protectors in low-voltage power grids. Countries around the world and the International Electrotechnical Commission have vigorously promoted the use of residual current-operated protectors in low-voltage power grids by formulating corresponding electrical installation regulations and...

AI Technical Summary

Problems solved by technology

The Chinese patent document with the application number 200420018274.5 and the name "Single-phase Electronic Leakage Detection Smart Energy Meter" discloses an electric energy meter that can detect and identify leakage current, but the electric energy meter cannot detect the leakage current value. Real-time measurement, and cannot record the leakage current in the user line

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