Wiring a Lamp and a Switch: The diagram shows a very simple configuration which can be used for powering a lamp, and the switching arrangement is also provided in the form of a switch. This provides the basic connecting data and the same may be used for wiring up other electrical appliances also (for example a fan).
Wiring a Lamp and a Fan in Parallel: Again the configuration employed is similar to the above and is just repeated for the fan. The input phase and the return path neutral are common for both the electrical gadgets or rather for all appliances that may be further included. Note that the fan speed regulator is also a load (mostly resistive) which should be connected in series with the fan and the switch. By adjusting the regulator knob we actually resist the flow of current into the fan thereby checking or varying its speed as desired.
Wiring up a Plug Socket: The wiring is no different from the above ones. Here the load points are just replaced with the socket terminals, or in simple words it’s an outlet for receiving the phase and the neutral potentials through a series switch placed in line with the phase.
Wiring up Heavier Loads: External loads like irons (presses), geysers, mixers, etc. normally have a plug and requires a socket to be plugged into, so sockets wired in the above manner can be used for powering these loads. However the socket/switch assembly and the wires used must all be appropriately rated. The recommended standards are a 3/18 (3 strands of 18 SWG each) for wires and 15 Amps for switch/socket. For smaller loads the specifications may be reduced to 1/18 and 5 Amps respectively.
Please note that although the above electrical house wiring layouts may look easy, there are a couple of things that needs to be taken care of. Firstly, for all configurations the switch must always come in line with the phase and before the load. Secondly the socket’s right side outlet should provide (or be connected) with the phase which again comes only after passing through the switch. Lastly but not the least, every house wiring system should incorporate a sound earthing line for providing the user total safety from residual or leaking body currents from a particular appliance.
The above argument can be understood through the following straight line diagram, see carefully the current path, after commencing from the phase source, it enters the switch, then the load and completes the cycle by ultimately getting back to the neutral point. The third path (earth) though inactive during most occasions, sometimes becomes an important parameter with old and over-used appliances for grounding any residual currents that may be leaking out from the bodies of these appliances.