Local Discharge Online Monitoring for Cables

1. Cable Testing Requirements and Preparations Prior to Testing

1）Prior to partial discharge testing, disconnect and ground the cable, leaving both ends suspended, and set up the safety perimeter fence.

2) Minimize the cable joint areaPTDisconnection of lightning arresters and other equipment.

3) Ensure the cable ends are clean and maintain sufficient insulation distance from the surrounding grounding parts.

4) Collect cable parameters such as length, model, type, and commissioning date.

5) Cable Length L: Measurement method for one side of the cable: 50m ≤ L ≤ 3km;

Measurement Method at Both Ends of the Cable:L＞3km。

2. Insulation Resistance Testing

The main insulation resistance test for the 10kV cable was conducted using a 2500V insulation megger, with no significant change in insulation resistance observed before and after the test; the insulation resistance for the 10kV cable's main insulation resistance test must be greater than 50MΩ to proceed to the next phase of testing.

3. Test the intermediate joint position of the cable and the cable length

AdoptSEBAKMT Easyflex ComMultifunctional Pulse Reflectometer (as shown in the figure)2) Conducted tests on the entire cable length and intermediate joint positions to measure cable length and joint locations, as well as to pre-locate faults such as short circuits and open circuits.

Testing Requirements:

1) The full length of the cable must be accurate for calibration purposes.

2) Ensure intermediate joint measurements are as accurate and detailed as possible, which is beneficial for determining the final location of partial discharge.

3) Measurement Range:50m～15000mThe measurement range needs to be adjusted according to the cable length.