The cable fault tester under UHV power can help many power workers conduct various power tests more conveniently.

The basic steps of a power cable fault tester are as follows: Typically, the following steps are tested:

(1) Identify the cause of the fault and the basic situation of the cable, such as whether the fault occurred during operation or during pre testing, whether it was a new cable or a longer cable, approximately the length of the cable, and whether there is a connector in the middle of the cable. Whether there are any faults, whether the cable is directly buried in the cable or buried in the cable trench, and the type of cable, etc.

(2) It must be clearly stated that both ends of the cable must be disconnected from other lines to ensure that the cable is not powered and the surrounding environment is in a safe state.

(3) Before each cable connection, the cable fault tester must pay attention to using a short-circuit wire to ground the phase wire of the cable. When discharging, one end of the short circuit must be grounded first, and the other end must be connected to each phase of the cable. For other electrical appliances, such as capacitors, test transformers, etc., attention should be paid to discharge and wiring before wiring and removing connecting wires. In short, it is important to develop operating habits and not be afraid of trouble. Before each operation, it is important to connect the electrical appliance to the circuit and discharge it before proceeding.

(4) When testing, first use the low voltage pulse function of the flash tester to conduct a full length test on each phase of the cable. When performing three relative armor tests, the test waveform is consistent. For most high impedance faults, the phase test waveform is consistent. For low impedance faults and high impedance faults with phase faults, the fault phase test waveform is not consistent with the length of the tested cable. Therefore, low-voltage pulses can be used to directly test the fault distance.

(5) When testing with high-voltage flashover method, whether the cable fault is a high resistance fault or a low resistance fault can be tested using high-voltage flashover method. For low resistance or wire breakage faults that can be directly tested for fault distance through low-voltage pulses, it is usually necessary to use high-voltage flashlights to verify the precise location of the test and fault point.

When using high-voltage flashover method for testing, attention should be paid to whether the cable is a single-phase fault or a multi-phase fault. When testing a faulty phase, other cable phase lines should be short circuited with the cable armor to reduce interference with other cables and improve testing accuracy.