Method for rapidly seeking low line electric leakage

Abstract

The invention relates to a method used to realize quick search of electric leakage in a low voltage circuit. The method, which eliminates the risk of breach of regulation and avoids the risk of accident during returning a residual current operated protective device, provides a systematic, scientific and effective method, thereby greatly increasing fault detection rate and saving a great amount of manpower and material resources. The method comprises the following steps: firstly, a phase line L1, a phase line L2, a phase line L3, a zero line N and the distribution transform low-voltage part of the power source of the prior system are completely cut off at K; a 220(380) V / 50V safety isolating transformer is adopted with the primary side connected with the power source; moreover, one end of the secondary side of the transformer is earthed, while other ends are in shorted connection with the phase line L1, the phase line L2, the phase line L3, the zero line N of an outlet line and then are connected with each other; then, a clip-on ammeter is adopted to respectively detect the leakage current of the four lines, thereby judging the line with electric leakage fault according to the value of I1, I2, I3 and IN; finally, the fault point of the line with electric leakage fault is detected according to the golden cut method.

Description

technical field [0001] The invention relates to a method for finding faults in a low-voltage power distribution network, in particular to a method for rapidly finding leakage of low-voltage lines. Background technique [0002] According to the requirements of "Technical Regulations for Rural Low-Voltage Power DL / T499-2001", the vast majority of rural low-voltage power networks in my country use TT systems and install residual current action general protection. The realization of residual current action protection is an effective measure to prevent residual current hazards in low-voltage power grids. However, due to the poor insulation level of rural low-voltage distribution networks, the residual current action protection device RCD often trips due to leakage, which affects power supply. But so far, there is no scientifically compliant method for finding faults. [0003] Existing methods are all searched in the case of returned RCD, but according to "Installation and Operat...

AI Technical Summary

Problems solved by technology

Moreover, the reliability is poor, and misjudgment is prone to occur, because the other two phases on the line are electrically connected to this phase through the electrical device and the neutral line, and there are often three-phase users on the line, and any switching of user equipment will affect Distribution of Leakage Current

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