1, oil-impregnated paper insulated power cables with oil-impregnated paper insulation of electric power cable. Its application with the longest history. It is safe and reliable, long service life and low prices. Main drawback is that laying head drop limit. Since development does not drip after impregnated paper insulation, solves the gap problem, oil-impregnated paper insulated cables can continue to be used.
2, plastic insulated power cable power cable insulation to extruded plastic. Commonly used plastic PVC, polyethylene, crosslinked polyethylene. Plastic cable structure is simple, easy to manufacture, light weight, installation is easy to install, without laying drop limit. Widely applied for low voltage cables, and has a tendency to replace adhesive impregnated paper cable. Its biggest drawback is there are branches of the breakdown phenomena, which limits its use higher voltages.
3, rubber insulated power cable insulation rubber with a variety of ingredients, extruded after a full mixing on the conductive core, formed after heat curing. It is soft, elastic, suitable for frequent moves, laying small bending radius for the occasion.
Commonly used for insulation rubber natural rubber-SBR rubber mixture of ethylene-propylene rubber, butyl rubber, and so on.