What function and significance does a three-pin plug serve?


There are switches and sockets with two or three pins. The 3-pin plug socket is designed for appliances that demand more power. Compared to 3-pin plugs, 2-pin plugs are used for appliances that demand less electricity.

Depending on the needs of the electrical appliances, both two-pin and three-pin plugs are utilised in India. The second pin is less effective than the third one if the device requires ground contact in a circuit. This is so that the user’s safety is guaranteed because the third pin controls the ground current.

Three-pin plug defined

An electrical appliance with three metal protrusions (pins) to connect to the socket is a 3-pin plug. The top, thicker pin of a 3-pin plug is used for connecting, earthing, or grounding. This earthing, or grounding, stops any potentially harmful overcurrent or residual electricity from flowing.

Connected electrical appliances that get too much electricity can be dangerous because they can harm the appliance and cause a short circuit. Earthing is therefore required to be done.

Three-pin plug’s functions

To connect and disconnect different electronic devices that need an AC power source to the main power supply and from it, a 3-pin plug socket is typically fitted.

The 3-pin plug, as suggested by its name, has three pins. Continue reading to learn what each of a plug’s three pins does.

The function of each of a plug’s three pins is:

1. A live pin (Line Connection)

The line connection connector (L), often the live pin, is used to power the appliances.

  1. 2. A neutral pin

The neutral pin (N) connects the device’s return paths to the return paths of the electrical outlet.

3. An earth pin

The top pin, which is the earth pin (E), is longer and thicker than the other two pins. Its purpose is to connect the metallic body of the device to the earth or the ground. This safeguards people and equipment by transmitting fault or excess current to the earth.

E, L, and N are typically designated with their respective functions on conventional three-pin plugs adjacent to them.

Applications and Uses for Three-Pin Plugs

1- Earthed and fused three rectangular pins

Class III electrical equipment is specifically built to conduct the rectangular-shaped three-pin plug type. Microwaves, refrigerators, and other appliances with metallic bodies are among them. All these appliances must be connected to the earth or ground. That will aid in removing this and reduce the chance of electrocution brought on by an electricity leak or an excess of current being transmitted to the metal body. Thus, providing additional protection against insulating failures safeguards users and equipment.

2- Earthed, three-round-pin plug

The round pin plug is specifically made to run large appliances like air conditioners.

Find out more at Legrand about three-pin sockets.