HZ-E High Voltage Bridge Cable Fault Locator

HV cable fault locator Overview

Power supply system always think that the cable fault location is more difficult. As the progress of the instrument, cable fault location become more convenient. In practice, choosing a reasonable instrument and experience is still important.
Typically, the power cable fault location is carried out in four steps
1, judge the type of fault
2, select the appropriate method and the corresponding equipment
3, rough measurement pinpoint
4, precise pinpoint

There are two kinds of methods: bridge method and wave reflection method. The wave reflection locator is more popular. But there are several cable failure is difficult to find with wave reflection method: For example, high-voltage cable jacket insulation defects, PVC cables, short cables, some high resistance damp failure.

The use of fault wire on both sides of the cable core resistance and proportional resistance constitute Murray bridge, is the traditional, classic cable fault location method, its application is almost synchronized with the use of cable, a hundred years of history. Positioning bridge equipment is low prices and simple operation, China has been widely used in the past. At present, a large number of applications of cross-linked polyethylene cable, after the breakdown, it is difficult to form a conductive area, breakdown point resistance is high, and even high voltage, flashover type breakdown. In the country to maintain the largest QF2-type bridge, the rated test voltage is only 500V, can not be high resistance fault location. And because of advances in electronic technology, wave reflection method has been popularized, so that the application of bridge method is gradually reduced, not known for new cable users, so the bridge method is almost forgotten.

HZ-E cable fault test bridge is to solve the power of the bridge to the high sensitivity of the interference problem. Measuring cable is dedicated high-voltage cable, the measurement principle is the method of four-terminal resistance, positioning accuracy of the bridge placed on the high side, and the operation of safe grounding. Completely solve the bridge method for high resistance positioning limitations, so that the bridge without dead zone, accurate and convenient features to play. This paper summarizes some of the applications of HZ-E cable fault test bridge positioning cable insulation and sheath defects experience for the majority of peer reference.