Why do some plugs have 2 holes?

A lot of plugs have two small holes, do you know why.

The neutral wire and the live wire allow the potential difference between the two ends, that is, the voltage, so that the electrons can flow before they can supply power.

Because some electrical appliances need to use two-pin plugs, and some electrical appliances need to use three-pin plugs. A two-pin socket is used to plug in a two-pin plug, and a three-pin socket is used to plug in a three-pin plug.

The binding posts in the two holes of the two-pin socket are connected with the live wire and the neutral wire (left zero and right fire) respectively. The two pins of the two-pin plug are connected to the two ends of the electrical part of the electrical appliance respectively, and when the plug is inserted into the socket, the electrical part of the electrical appliance is connected with the live wire and the neutral wire.

The three holes of the three-pin socket are distributed in an isosceles triangle, the binding posts in the two jacks at the bottom corner are the same as the two-pin plugs, which are connected with the live wire and the neutral wire respectively, and the binding posts in the jack at the top corner are connected to the ground wire.

The three plugs of the three-pin plug are also distributed in an isosceles triangle, the two prongs at the bottom corner are the same as the two-pin plugs, connecting the electrical part of the electrical appliance, and the prongs at the top corner are connected with the metal shell of the electrical appliance. When the plug is inserted into the socket, not only the electrical part of the appliance is connected with the live wire and neutral wire, but also the metal shell of the appliance is connected to the earth.

The two-prong socket is an outlet without grounding protection. There are only two terminal blocks in ln.

Three-hole, is a socket with grounding protection, with L, N, and grounding three terminals, usually used in equipment with metal shells, to prevent insulation damage and leakage during use.

There is also a four-prong socket for three-phase electricity.

The two-jack socket does not come with a ground wire.

The three-jack socket has a ground wire. Sockets with ground wires can provide an extra layer of protection. Prevent electricity leakage from hurting people.

Of course, it is useless if there is no well-installed grounding wire. Nowadays, many electrical appliances generally use three-pin sockets.

In fact, with the current process, any shape can be used. The reason for the two holes is that one hole cannot form a loop (one hole can be made after the process is improved), and there is no need for a third hole with a neutral line.

A lot of plugs have two small holes, do you know why.

Why are there two small holes in the plug? After listening to the old electrician, I realized that the child at home always played with the plug with such a powerful effect, worried that he would be electrified? Find this mechanism, play for as long as you want, the small hole in the plug, is clamped by the spring, it is not easy to fall, wear it with a rope, and prevent the child from getting electricity.

Exhausted, it is not easy to suffocate.

Hey, why are there three in my family?

I don't understand what you mean, please say it again, okay?

Many students will ask why there are often two on the two-pin plug.

What about holes? Of course, this is not used to add a small lock as mentioned in the funny back**, but because the metal contacts of many plugs are relatively thin, and the contacts are clamped by two elastic metal sheets after inserting the jack, but they are easy to loosen. With the addition of these two holes, the metal contacts can be snapped together with the protrusions on the metal sheet, making it difficult for the plug to fall off.

Some newer electrical appliances have no small holes in the contacts of the two-pin plugs, because they increase the thickness of the contacts, which aggravates the deformation of the metal sheet in the jack, and can also achieve the effect of increasing the friction in the jack. As for the three-pin plug, it has the unique stability of the triangle, so there is no need to worry about it falling off the socket easily.