The high-voltage bridge fault tester is designed based on the principle of MURRAY bridge and is suitable for locating the breakdown points of various wires and cables after laying, as well as defect points with low insulation resistance values but no breakdown, and locating faults in the outer sheath of high-voltage cables. Of course, it can also be used for defect location of various cables in cable factories.

The equipment adopts a switch power supply to form a high-voltage constant current source, and uses a high-sensitivity amplifier and ammeter to indicate balance. It forms a balance bridge with a proportional potentiometer and is placed at a high potential as a whole. The test line is a specially designed dual core high-voltage rubber cable, which uses a four terminal resistance measurement method to avoid errors caused by lead resistance. The operation button on the panel is at ground potential, and the bridge is operated through an insulating rod. The high-voltage constant current source and bridge are integrated into a portable device.

The high-voltage bridge fault tester has three functions:

1. DC withstand voltage test: The equipment can output a DC voltage of 0-15kV and can be used for cable DC withstand voltage test.

2. Burn through fault point: Burn through and reduce the resistance of high resistance and flashover fault points.

3. Fault pre positioning: Using the bridge principle for pre positioning, the four terminal resistance measurement method avoids errors introduced by lead resistance.  

Meanwhile, the high-voltage bridge fault tester is particularly suitable for:

The high resistance piercing points of the cable after laying, especially the linear high resistance piercing points that are difficult to burn into low resistance, such as the linear high resistance piercing of the middle joint of the cable.

Flashover type breakdown point, after breakdown, the constant current source can maintain the arc, and a stable current passes through the bridge, which has sufficient sensitivity.

Defect points that have not yet been broken down but have low resistance, such as insulation defect points found with a megohmmeter that have low cable resistance but do not break down under operating voltage.