The socket is designed to connect portable devices with a power of several kilowatts to the network. So that surrounding objects do not get under voltage, it is made as a female connector. It is always used in conjunction with a plug with metal pins. Execution can be the most diverse. An important criterion when choosing is the size of the outlet, determined by the diameter and shape of the holes for domestic and foreign species.
Types of electrical outlets
For a conventional 220 V network, sockets are made two-pin. They mostly provide grounding. The simplest models are designed to work in dry rooms. They can be recessed for concealed wiring or overhead for open. More complex designs provide protection against 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 special skills.
How does the outlet work?
The principle of operation of the electric plug connector is simple: when the plug is inserted into the socket, two contacts are closed and electricity is supplied to the device.
Ordinary household sockets are designed for a current of 10 A or 16 A. A more powerful device can not be connected to them, since the machine will turn off in the panel or in the worst case, the plug connector will fail.
It is better to connect household appliances with increased power directly to the power line, where the machine is installed in the control panel.
For low-current lines, their own connectors are used, through which the phone, computer, video and audio wiring, etc. are connected.
How is the power outlet?
The design contains a block (base) with metal pads on which the supply wires and contacts are fixed. All connections are protected by a plastic case. The plug must not only be connected to a power outlet, but also prevented, along with the flexible wire, from falling out through spring-loaded ground contacts. They are installed in many types of outlets. In order for the grounding to work, in the apartment it is necessary to lay a third wire connected to the ground of the interfloor shield.
Power wires are connected via screw connections or self-tightening contacts.
Protective shutters are installed in the openings of the case of some models of outlets. In the absence of a plug, the conductive parts are closed. When it is inserted into the openings of the housing, the shutters are pushed back under pressure to provide contact with the contacts. They can also be opened manually.
Various devices are inserted into the model: push-buttons, plugs, covers, lights, residual current devices, switches, etc. At the same time, the overall dimensions of the outlet can increase.
Materials
The first pads were made ceramic, but now carbolite is predominant. Plastic may deform when heated, and the breakdown voltage is less. The advantage is lower price.
The case is made of durable plastic, which is often designed for the interior in shape, color or special inserts. Modern models are equipped with interchangeable linings for the interior of the premises. In this case, the electrical part is not necessary to change.
The main elements of the outlet are metal contacts. Through them, electrical energy is transmitted from the power wires to the appliance. The material used is bronze or brass, which have elasticity to ensure reliable contact between the pins of the plug and the socket. In addition to mechanical properties, the electrical parameters of the metal conductive parts are important, what voltage and current they are designed for. Here, both the material and the size of the socket and plug are of importance: the cross section of the pins and holes for them.
Outlet classification
Most often, recessed sockets are used. They are mounted in a wall with which the surface of the housing is flush or protrudes slightly. One niche will not be enough. There should be installed a socket, in which the model is screwed directly to its body or with steel legs, which are also pushed apart by a threaded connection. For installation in drywall, a different type of mounting box is used, where its fastening to the sheet has distinctive features. According to the size of the installation of outlets, holes are cut out in the sheet in which the socket boxes with four screws are inserted.
An external outlet (bill) is mounted directly on the wall and is designed for open wiring. Inside, both types of products have similar designs.
The number of poles of a standard outlet is usually two. There is also a grounding contact. It is an important safety feature that should not be neglected. This is especially true for rooms with high humidity, where in addition to grounding an RCD must be installed.
To connect three-phase devices, multipolar 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 stiffness of the connection is stable, and wear is minimal. The petal connections during operation become weaker and when the plug is inserted, it can spark, which leads to burning of the contacts. Nowadays, modern petal designs have been developed in which the connection does not loosen with frequent use.
In the design of the double outlet, two plugs are connected . In this case, one standard block is used, suitable for one mounting box. The installation size for the dual-type outlet and its connection scheme are the same as for a single.
There are also triple sockets or whole blocks. They incorporate switches, outputs for the Internet, telephone, dimmers, additional protection against electric shock, etc. 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 that look like ordinary ones, and if necessary they are removed from the housing and transferred along with the wire to the right place.
Important! The sizes of sockets and switches should be suitable for the installation boxes. Upon purchase, they should be selected immediately to create a reliable connection.
Standard outlet sizes
General international standards for sockets have already been created, but there are still many differences. In different countries, the size of the outlet, the distance between the pins and their shape may vary. The wiring diagrams are basically the same, due to their simplicity. Many of them do not fit domestic forks with round pins, if flat are provided. Differences can be in the number of holes and the distance between them. The dimensions of all are approximately the same.
The standard size of the built-in outlet is 185x190x85 mm. If it contains grounding contacts, the dimensions increase slightly: 230x190x85. The connection diagram is also changing, as the third wire appears.
Features of domestic models
Domestic Soviet 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).
For the most part, they have been replaced with type C6 with a pin diameter of 4.8 mm (European standard). They already have a ground contact. The basis for the development was the German standard. If a spring contact is installed here, plugs of types C5 and C6 will fit the outlet.
The current size of the outlet is smaller than that of the old metal sockets, which are recommended to be replaced, otherwise the steel legs of most models will not hold them in the opening. You can use gaskets, but they will not last long.
Conclusion
To select and install hardware with wiring, you must follow the necessary rules and follow well-known standards. The most important thing is compliance with safety regulations. All repairs are carried out with the power off. The socket is selected with the necessary functions and the specified power.