Why is there a metal hole in the plug if the sockets do not have a pin?

Not everyone knows, but everyone saw a strange hole in the fork. We use it every day, but we do not fully understand what it is for. I wanted to tell in the article about this strange element.

The question arises: "If there is a hole, then where is the pin in the socket or what should go there?" I reviewed all the sockets in the house, but found nothing.

This is because the sockets that are used in Russia do not have any pin, but there is a hole in the plug.

In Russia, Asia, South America, Germany, Norway and other countries, the following standards are common: socket type F and C, which are designed for 220-240 V.

Type F (Schuko) - protective contact, where the socket and plug are presented with protective earthing contacts. This is implemented in the form of staples and there are no protruding pins.

Many people confuse such a plug (Schuko) and call it incorrectly - "Euro plug".

Most of these forks are hybrids (CEE 7/7). They have that same hole for the grounding pin. I found such holes on a fork from a kettle, iron, multicooker and other modern household appliances.

In France, Czech Republic, Belgium, Poland, you can see another socket type (E). Two round contacts and a tab (pin) at the top of the socket. The socket is suitable for CEE 7/7 plugs as well as CEE 7/17 and CEE 7/16.

Strange prongs in a socket have several functions at once

1. Strengthening fixation. The plug sits even more firmly on the outlet, it is more difficult to pull it out. Looking closely at the fork (hole), you can see the petals that clamp the pin like in a vice.

2. Grounding is the main function.

3. Such a device will not make it possible to confuse the polarity of the plug. With this strictly abroad.

Did you know what the hole in the plug is for?