A three-pin plug refers to any plug that comes with three pins. Three-pin plugs are considered a safer option because in addition to the two live wires found in a two-pin plug, they come with a third "neutral" pin that channels away any leaking voltage.
Inside a three-pin socket, there are three pins designed to carry different wires. The red or brown wire represents the live line, the blue or black wire represents the neutral line, and the green or yellow wire represents the Earth. The case of the socket is typically made of tough plastic or rubber, which serves as an insulator.
To wire a three-pin socket, installers will need a screwdriver. They will also need to bare the end of the three wires by stripping an inch of flex from each tip. It is important that the wires be connected in their right positions. The Earth wire is screwed in the 12 o'clock position while the neutral wire connects in the 9'o clock position. The live wire is connected in the 3 o'clock. Its position can also be identified by the presence of a fuse, which separates the wire from the pin. It is also important to ensure that the cable is properly held down in place by the cable grip at the base before closing the plug.