Study on electric arc´s on-line detection and warning system for low voltage distribution box

The switch contacts and connection terminals of low voltage distribution box can arouse arc fault easily for the bad contact. The arc fault not only can affect the normal power supply, but also can arouse electrical fire probably. In order to check arc fault reliably, the arc voltage signal and arc light intensity signal are separately detected. This technology is the domestic first. Extract input and output line voltage of the distribution box, convert them into frequency signal respectively, and compare them to gain the arc voltage signal. Put the arc voltage signal and arc light intensity signal into the advanced single-chip microcomputer, PIC16F877, to analyze and estimate synthetically. The arc fault on-line detection and warning system not only can check and forecast the electrical fault of low voltage distribution box, but also can early warn the hidden danger of electrical fire.