Electrical plugs provide users with a physical, easy-tohandle plastic connector that acts as a bridge between an electrical appliance’s power cable and the mains electrical grid. Plugs come in a variety of shapes and sizes - as do their equivalent sockets - but all share a couple of basic characteristics and a selection of standardised technology.
Each plug has either two or three separate wired contacts, each of which is contained within a thick, insulated cable. These contacts are commonly made from steel or brass, as they are good conductors, and coated with zinc and nickel. The first contact is referred to as the ‘line’ or ‘live’ contact and terminates at the live terminal at the right-hand side of the plug. The live wire carries current from the source to the load and vice versa, as the predominating form of electricity delivered to households is alternating current (AC), where the current changes direction up to 60 times per second.
The second wire is referred to as the ‘neutral’ contact and terminates at the neutral terminal, which is positioned parallel to the live terminal on the left-hand side of the plug. This contact completes the circuit running through the load in order to generate the necessary power to run it. As with the live contact, current from the source frequently enters and exits the load multiple times per second via the neutral contact. However, unlike the live contact it remains at the voltage potential of the third wired contact, the ‘earth’.