6. What inspections should be carried out before the cable is laid?

A:(1) The bracket should be complete and the paint should be complete.

(2) Cable type, voltage and specifications conform to the design

(3) Cables are well insulated and should be judged by dampness when there is suspicion of the sealing of oil-paper cables; directly buried cables and small bottom cables should be difficult to pass the DC withstand voltage test; and oil samples of oil-filled cables should pass the test.

 (4) the oil pressure of the oil filled cable should not be lower than 1.47MPa.

 7. When doubting the sealing of oil-paper insulated power cables, how to check if the insulated paper is damp by a simpler method?

A: Ignite the cable insulation paper or put it into the cable oil of about 150 °C for inspection. There is no “click” or white foam, indicating that it is not damp.

8. What should be indicated on the cable signage? What are the requirements for writing?

 A: The sign should indicate the design number, cable type, specifications and starting point of the cable line, and the cable used in parallel should have a sequence number. It requires clear handwriting and easy shedding.

9. How to make the moisture trapping treatment before the construction, the yellow wax ribbon, the black glass paint ribbon, the alkali-free glass ribbon, etc.

  A: (1) Constant temperature drying method: the insulating tape is rolled into 25-30mm coils, put into 110-120 C constant temperature drying box and bake for 4-5h, cool and dry out, put into a dry sealed cylinder.

 (2) Oil immersion dehumidification method: put the small coil of insulating tape into the cable oil with constant temperature between 120 and 130 degrees, keep 30 mm away from the bottom of the pot, after a certain period of time, the oil surface will no longer produce foam and take out, and put it into the barrel with cable oil, the oil level should exceed all the objects loaded and seal it.

10. What is the role of the inner sheath of the cable?

A: The insulating layer will not be in contact with water, air or other objects to prevent the insulation from dampness and mechanical damage to the insulating layer.