A material that allows energy to flow with relative ease is known as a conductor. The most common form of electrical conductor used is the wire. Most electrical wires are made from copper or aluminum and are in one of two forms: solid or stranded.
The term electrical cable usually refers to multiple insulated wires grouped together in a common sheathing (Figure 1).
- Electrical cable components
- Stranded flexible conductor
- Wire strippers
With wire strippers, you can strip the amount of wire required for the type of connection being made. It is important to avoid damaging the copper wire by nicking the copper or cutting into it. Nicked wires can lead to overheating and eventually could cause an electrical fire.
Most electrical wiring circuits look complicated because several wires are found at any one point in the circuit. In order to make it easier to know exactly which is which, wires are identified by colour or labelled.
For building construction, the Canadian Electrical Code reserves two colours for specific applications:
- White or natural grey covering is reserved for insulated, identified conductors; identified common conductors; and identified neutral conductors.
- Green covering is reserved for the equipment grounding conductor.
When this system of colour coding is followed, at any point in any circuit a white wire always indicates a neutral conductor. A green wire always indicates an equipment grounding conductor. Any other colour wires, such as red, black, or blue, can be assumed to be live or hot, meaning that they will have a voltage on the conductor and are therefore dangerous.
Wires are manufactured in sizes according to the American Wire Gauge (AWG) system. The cross-sectional area of each gauge is an important factor for determining the current-carrying capacity of a wire (ampacity). Increasing gauge numbers denote decreasing wire diameters, ranging from the largest 0000 (4/0) to the smallest, 44.