Power cable line selection scheme

Before the DC withstand voltage test

Self-regulation

1000V megger for rated voltage 0.6/1kV cable;
2500 megohmmeter (6/6kV) for cables above 0.6/1kV
And above cable can also be used 5000V megohmmeter)

1) 1 to 3 years

2) After the new terminal or connector

1) Test voltage value as specified in the following table, pressurization time 5min, no breakdown

The leakage current of cables of 6/6kV and below is less than 10μA, and the leakage current of 8.7/10kV cable is less than 20μA, the imbalance factor is not specified.

Rated voltage Uo/U(kV)

Viscous oil paper insulation test voltage kV

Non-drip oil paper insulation test voltage kV

0.6/1

4

4

1.8/3

12

——

3.6/6

twenty four

——

6/6

30

——

6/10

40

——

8.7/10

47

30

21/35

105

——

26/35

130

——

1) After overhauling the new terminal or connector

2) When necessary

It is recommended to use the resonant frequency withstand frequency of 20Hz~300Hz for each voltage level. The test voltage and time are as follows:

1) If the test conditions are not available, the normal system can be used instead of the ground voltage for 24h.

2) When necessary, such as: suspected cable failure

Voltage level

Test voltage

time

35kV and below

1.6UO

60min

110kV

1.36UO

60min

220kV~ and above

1.12UO

60min