The socket is designed to connect to the network of portable devices, the power of which reaches several kilowatts. So that surrounding objects do not get under voltage, it is made as a female connector. It is always used in tandem with a plug with metal pins. Execution can be very diverse. An important selection criterion is the size of the rosette, determined by the diameter and shape of the holes for domestic and foreign types.
Types of electrical outlets
For a regular 220 V network, sockets are made two-pin. Most of them are grounded. The simplest models are designed to work in dry rooms. They can be recessed for hidden wiring or overhead for open wiring. More complex designs provide protection from dust and moisture, are made double, may contain switches and built-in RCDs. The purpose and principle of operation remains the same. The design allows you to supply electricity to the device to any person who does not have specialskills.
How does an outlet work?
The principle of operation of the electrical plug is simple: when the plug is inserted into the socket, two contacts are closed and electricity flows to the device.
Ordinary household sockets are designed for a current of 10 A or 16 A. A more powerful device cannot be connected to them, because the machine in the shield will turn off or, in the worst case, the plug will fail.
High-power household appliances are best connected directly to the power line, where the machine is installed in the control panel.
For low-voltage lines, their own connectors are used, through which a telephone, computer, video and audio wiring, etc. are connected.
How does a power outlet work?
The design contains a block (base) with metal pads on which the lead wires and contacts are fixed. All connections are protected by a plastic case. The plug must not only be connected to the outlet, but also held together with the flexible wire from falling out through the spring-loaded ground contacts. They are installed in many types of outlets. For grounding to work, it is necessary to lay a third wire in the apartment, connected to the ground of the interfloor shield.
Power wires are connected through screw connections or self-tightening contacts.
Protective shutters are installed in the openings of the body of some socket models. In the absence of a plug, the conductive parts are covered. When it is inserted into the openings of the case, the shutters move under pressure, providing communication with the contacts. They can also be opened manually.
Various devices are inserted into the model: plug ejection buttons, covers, lights, residual current devices, switches, etc. In this case, the overall dimensions of the socket may increase.
Materials
The first pads were made of ceramic, but now carbolite prevails. Plastic can be deformed when heated, and its breakdown voltage is less. The advantage is the lower price.
The case is made of durable plastic, which is often designed to match the interior in shape, color or special inserts. Modern models are supplied with interchangeable linings for the interior of the premises. At the same time, it is not necessary to change the electrical part.
The main elements of the socket are metal contacts. Through them, electrical energy is transmitted from power wires to an electrical appliance. The material used is bronze or brass, which have elasticity to ensure reliable contacts between the pins of the plug and the socket. In addition to mechanical properties, the electrical parameters of metal conductive parts are important, for what voltage and current they are designed. Here, both the material and the size of the socket and plug are important: the cross section of the pins and holes for them.
Classification of outlets
The most commonly used recessed sockets. They are mounted in a wall with which the housing surface is flush or protrudes slightly. One niche will not be enough. There must be a socket in which the model is screwed directly to its bodyor steel paws, bred to the sides also with the help of a threaded connection. For installation in drywall, a different type of mounting box is used, where its attachment to the sheet has distinctive features. Holes are cut out in the sheet to fit the dimensions of the sockets, in which the sockets are inserted with four screws.
External socket (consignment note) is mounted directly on the wall and is designed for open wiring. Inside, both types of products have similar designs.
The number of poles in a standard outlet is usually two. There is also a ground connection. It is an important safety element that should not be neglected. This is especially true for rooms with high humidity, where, in addition to grounding, an RCD should be installed.
To connect three-phase devices, multi-pole sockets (up to four) are used. Contacts are made round and rectangular. The pins are pressed with petals or springs. The latter are more reliable, since the rigidity of the connection is stable, and wear is minimal. The spade connections become weaker during operation and when the plug is inserted, it can spark, which leads to burning of the contacts. Now modern petal designs have been developed in which the connection does not come loose with frequent use.
The double socket design connects two plugs. In this case, one standard block is used, suitable for one mounting box. Installation dimension for a double-type socket and its diagramconnections are the same as for single.
There are also triple sockets or whole blocks. Switches, Internet, phone, dimmers, additional protection against electric shock, etc. are built into them. If the socket is used often, it makes no sense to pull it out and insert it every time. For this, a model with a built-in switch is selected.
Extension sockets are used, which look like ordinary ones, and if necessary, they are removed from the case and transferred along with the wire to the right place.
Important! The dimensions of the sockets and switches must match the installation boxes. When buying, they should be selected immediately to create a reliable connection.
Standard outlet sizes
Common international standards for sockets have already been created, but there are still many differences. In different countries, the size of the socket, the distance between the pins and their shape may differ. The connection diagrams are basically the same, due to their simplicity. Many of them do not fit domestic plugs with round pins, if flat ones are provided. Differences can be in the number of holes and the distances between them. All are approximately the same size.
The standard size of a built-in socket is 185x190x85 mm. If it contains ground contacts, the dimensions increase slightly: 230x190x85. The connection scheme also changes, as a third wire appears.
Features of domesticmodels
Soviet Soviet plug sockets are still preserved, the pin sizes for which are 4 mm, and the distance between them is 19 mm (type C5, without grounding contacts).
Most of them are replaced by C6 type with 4.8mm pin diameter (European standard). They already have a ground connection. The basis for the development was the German standard. If a spring contact is installed here, the socket will accept C5 and C6 plugs.
Modern size of the socket is smaller than the old metal sockets, which are recommended to be replaced, otherwise the steel paws of most models will not hold them in the opening. Gaskets can be used, but they won't last long.
Conclusion
To select and install fittings with wiring, you must follow the necessary rules and follow well-known standards. The most important thing is the observance of safety regulations. All repairs are carried out with the power off. The socket is selected with the necessary functions and the specified power.
