Xhhg521A Factory Price Digital Bridge Method Underground Cable Fault Sheath Prelocator

Introduction
The cable outer sheath fault tester XHHG521A is designed based on the MURRAY bridge principle and can be used to locate the breakdown points of various wires and cables and the defect points that have no breakdown but low insulation resistance values.

To create a high - voltage constant current source, the equipment uses both an electric voltage regulator and an R - type transformer. Button operation enables the increase or decrease of voltage. With a no - load voltage of 7,500V and a short - circuit current of 100mA, the device uses a high - sensitivity amplifier and galvanometer for balance indication. It forms a balanced bridge together with a proportional potentiometer, and the whole system is placed at a high potential. A specially designed two - core high - voltage rubber cable serves as the measurement cable. By using the four - terminal resistance measurement method, lead - resistance - caused errors are avoided. The entire panel is at a low potential. One - touch operation lets users enter the cable length and get the fault distance automatically calculated. The high - voltage source and bridge are housed in a portable protective box. As a result, the device has high voltage, is lightweight, easy to operate and safe to use.

High voltage bridges are particularly suitable for
1. The high-resistance breakdown point of the cable after laying, especially the linear high-resistance breakdown point that is difficult to burn into low resistance, such as the linear high-resistance breakdown of the cable intermediate joint.
2. Flashover type breakdown point. After breakdown, the constant current source can maintain the arc, a stable current flows through the bridge, and the bridge has sufficient sensitivity.
3. Defects that have not yet broken down but have low resistance, such as insulation defects found with a megohmmeter that have low cable resistance but do not break down under the operating voltage.