How to point  if voltage discharge can not breakdown of  HV high resistance fault  ?
According to the resistance value of cable fault point, it can be divided into cable high resistance fault and cable low resistance fault.When the dc voltage withstand test of cable high resistance fault is carried out, the leakage current of the cable changes little when the test voltage is increased. When the voltage rises to a certain value, the cable fault hits through and the leakage current increases suddenly. The breakdown voltage obtained by repeated tests is basically the same.This kind of cable fault is called breakdown high resistance cable fault.This kind of breakdown cable high resistance fault with two pulse or three pulse cable fault tester with impact discharge method can quickly and accurately locate the location of the fault point, such as the our multiple impulse coupler PCLC-900C three level multiple pulse cable fault tester.