An underground cable essentially consists of one or more conductors covered with suitable insulation and surrounded by some protective layer. Normally, electric power can either be transmitted using overhead lines or underground cables. The underground cables have several advantages such as less liable to damage through storms or lightning, low maintenance cost, fewer chances of faults, smaller voltage drop, and better general appearance.
Underground cables are usually classified according to their Voltage ratings.
They’re grouped as follows :
1. Low tension cables which have a maximum voltage handling capacity of 1000V
2. High tension cables which have a maximum voltage handling capacity of 11kV
3. Super tension cables which have a maximum voltage handling capacity of 33kV
4. Extra high tension cables which have a maximum voltage handling capacity of
66kV
5. Extra super voltage cables which are used for applications with voltage
requirement above 132kV.
Electrical power cable terminations
The electrical cable termination is the physical and electrical connection of a cable end that connects to another cable, or to the terminal of the equipment. The common type of terminations are crimp connection, soldered connection, compression termination, and wire-wrapping connection, direct connection, loop or eye connection. Some of the factors that
Determine the type are:
- Outdoor or indoor use
- Voltage
- Current
- Overhead, or underground
- Type of Connector on the equipment where the cable will be connected.