Extension cord wiring diagram
An extension cord also called an extension lead or power extender is a power supply expanding the box. It is a lengthy flexible electrical cable with a plug at one end and multiple sockets on the other end. And each of the sockets is independently controllable via separate switches. It is similar to the wiring of a switch box which is connected to an extended input supply cable.
To make an extension cord, get an electrical wire with appropriate length. The length of cord should be considered, based on the requirements. Try to choose the minimum length as required. Because the length increases the electrical resistance and thereby the copper loss. So, every extra length of cord reasons for power loss in the conductor. The increase in length creates a voltage drop across the cord and decreases the amount of power that can deliver by the cord. Thus, use a cord length that maintains the requirement and also not in excess.
Connect each neutral and earth pole in the sockets, in parallel to the main neutral and the earth. Distribute the phase line to the phase poles of the sockets via individual switches. Usually, all the socket will be similar to match the plug of extension cord. Use socket types, that suits the load’s plug. Or use multiple types of sockets.
The wires and the parts should satisfy the power requirements. Depending the loads which may be used, choose a cord cable with proper wire gauge. Extension cords should have a minimum of 16 AWG. And the rated load power should be at the limit of amperes the chord can drive. If available, it is recommended to wire circuit with standard colour codes. Because it helps to identify the lines during wiring and also if any chance of maintenance occurs. Commonly phase, neutral and ground connections have red, black and green respectively. The colour codes followed may vary with countries, in most countries ground connection has green. But for phase and neutral different colours are using.
Always make sure the extension cord has no any overload condition. To protect the cord from over current, install a fuse inside the extension cord for the rated power capability. A fuse can be added in the phase line before the first switch in the circuit. Additional options such as Fuse/Mini MCB, power-on indicator, etc, can be included with the extension box.
Keep extension cord cable protected from physical damages. Make sure it has proper insulation and avoid chances of contact with water or wet surroundings.
Also, the cord should not have rolled or coiled while in use. The coiled structure causes inductive reactance or impedance across the coil and drops voltage across the wire.
Components Required for Extension cord
|Switch||SPST, 250V , 5A||Nos|