The maximum short-circuit current thermal effects produced by the role of time, should not undermine the continued use of the cable characteristics. For non-fuse protection circuit, according to the short-circuit current core temperature does not exceed a Linear Section 2.4 of the Schedule are allowable values, namely cross-linked polyethylene (XLPE) insulating power cable cores maximum temperature of 250 ℃.

According to the application, laying location, and working conditions of marine cable to select the appropriate marine cable.

Appearance of building wire Smooth and round, uniform color, rubber insulation and copper conductor closely difficult to peel, bad quality rubber insulation looks thick, but after squeezing, the squeeze point will turn into white, it is easy for cable aging and fall off lead to electric leakage loss in the future.

For XLPE high voltage electric cable, the cable inside watered, especially the water inside the inner liner, it is very dangerous, because XLPE insulation afraid of water, under the influence of high voltage electric field, the water will make XLPE insulation water trees again produce electrical trees, resulting in cable insulation breakdown.

High voltage power cable is a kind of cable used in special occasion, we should obey operation rules strictly when using, once accidents happened, the consequences are very serious. High voltage power cable once watered, under the influence of electric field, aging will occur, leading to cable breakdown.

ACSR Conductor is stranded together by aluminum wire and steel wire, which is widely used in overhead transmission lines, its quality directly affects the safety of electricity delivery. This paper will discuss the main reasons and improved methods that affecting the quality of ACSR conductor.

For HV Power Cable below 35KV, carrying capacity calculation is same as general power cable. For 35KV HV Power Cable and above, carrying capacity should be calculated according to the economic current density.

There are two kinds of power transmission lines are used currently, one is the most common overhead transmission line, which generally uses non-insulated bare conductor through the ground towers stand as a support, it will lead to the suspension tower with insulators; another is power cable transmission line, which producing by a special process, laying underground or laid in cable tunnel.

If overhead bare conductor cables are arranged vertically, the distance between lines to be bigger than the horizontal arrangement, because the wire swinging up and down swing is larger than the horizontal. Such as the prescribed distance between 6KV overhead bare conductor arranged vertically is 1m, it is 0.7m horizontally.

Flexible towline cable can not twist within laying, that is the cable can not be unfasten from one end of the cable reel or cable drum, and it should rotate the reel or drum to expand the cable, if necessary, cable can be expanded or suspended.