Designation of sockets and switches in drawings and diagrams

Any type of electrical installation work is carried out in accordance with the work project.It contains instructions for placing equipment and electrical wiring elements at the site.

The symbols for sockets and switches in the drawings have a single standard. This eliminates confusion and clearly demonstrates any nuances of installation work.

Regulatory documents

So that a specialist of any category can navigate the project, SNiPs and GOSTs were developed, which regulate, among other things, the designation of various types of sockets and switches on drawings and wiring diagrams. One of them is GOST 21.210-2014.

All types of devices presented in the form of simple geometric shapes for ease of depiction and reading. To standardize the type of symbols, they use the documents of the International Electrotechnical Commission (IEC), and in particular the IEC 60027 standard.

Conventionally, the graphic designation of a single-key switch with open installation on a circuit diagram and an electrification plan has a significant difference

However, the presentation of electrical wiring is made in different types of documentation and has some differences. For example, the appearance of a socket and switch on a construction drawing and a connection diagram has a significant difference, since these documents have different purposes.

Main types of sockets

An electrical outlet (plug socket) is a device that allows you to quickly connect and disconnect various devices from the network.

Its main elements are:

• contacts – provide connection between the electrical network and the plug;
• block – ceramic housing for contacts and fastenings of the installation box (socket box);
• frame – plays a decorative and protective role.

In the general sense of the word, the product can perform other functions. For example, connecting and disconnecting telephone communications, radio, Internet and even water supply in plumbing fixtures. Consequently, there are many structural and functional varieties of this type of connection.

The main types of sockets used in everyday life vary:

• depending on the installation method, there are overhead and built-in;
• by the number of nests - single or a block of two, three or more;
• by the number of connections - with and without a grounding contact;
• by purpose - antenna, for telephone and Internet, for household appliances, for powerful equipment.

Easy and universal to install surface-mounted device. It does not require making deep holes in the wall, which is convenient for temporary placement or in industrial premises. The housing together with the block is attached to the desired surface and connected to open electrical wiring.

Since the installation is not carried out in the installation box, ordinary dowel nails are suitable for reliable fastening to the plane.

The built-in installation option has a more aesthetic appearance, since the main part of the product is immersed in the wall, and only the protective casing remains outside. Thus, nothing interferes with the perception of the interior of the room.

The wiring in this case is also rather hidden. For this type of fastening, a cylindrical hole is cut in the wall into which the installation box is mounted. It securely and securely fixes the socket in the wall.

According to the rules, it is recommended to install a device with a grounding contact at a distance of at least 500 mm from the gas pipeline

The version with two sockets is designed to connect two plugs to the network at once. With hidden installation, the block is placed in one socket box.

To increase their number (more than two), you will have to make an additional hole in the wall and combine the body with one frame if hidden installation is planned. If the model is overhead, then modular pads are added.

The European standard provides for the installation of an electric point at a height of 30 cm from the floor. This allows you to quickly find it in the dark by touch and comfortably use it for a person of average height

The modern type of socket is with a grounding contact. Used in networks with a grounding wire, which are safer than “phase-neutral” networks.

Additional terminals are attached to this wire. They first come into contact with the plug being connected, which prevents dangerous voltage and current from damaging faulty household electrical appliances. It also protects the equipment from network interference and electromagnetic interference from other devices.

The antenna has no voltage. It is used to connect the TV to the antenna cable. The only external difference is the appearance of the inlet hole in the housing.

It makes sense to place the socket block behind the TV if the location of its installation has been determined in advance, so as not to further clutter the space with cables

A computer socket is used to connect to the Internet and local networks. You can also connect a telephone cable to it.

The Internet and telephone cable connectors are the same in shape - RJ45 and RJ11/12, respectively. The first uses 8 contacts, and the second 4 or 6. But to connect to the Internet through a telephone jack, you will have to use a modem that uses a Dial-up connection.

Manufacturers of Internet cables do not recommend unwinding twisted pair cables larger than 13 mm when connecting to avoid problems connecting to the Internet.

Such devices can be made in a compact case or have the appearance of a regular 220 V. To connect a telephone with an old-style connector, you will have to install a socket with the appropriate input.

Equipment protection degree

Sockets, like any electrical equipment, have varying levels of protection against contact of live parts with solid particles and water. This ensures safe human use in a variety of conditions.

To mark the degree of protection, a combination of two letters (IP) and two numbers is used. IP - International Protection, which translates from English as “international protection”. And the numbers characterize its level.

For example, the degree of protection IP20 according to GOST 14254-2015 can be deciphered as follows:

• first digit 2 – current-carrying parts of the product are inaccessible to objects 12.5 mm thick or fingers;
• the second digit is 0 – water may get inside the device.

The degree of protection IP23 means that fingers cannot get inside, and the angle of safe drops falling onto the body is 60 degrees.

Conventionally graphic designation

GOST 21.210-2014 unifies the representation of electrical elements on diagrams.Makes them universal throughout Russia.

The designations of sockets presented in this document can be divided according to several criteria:

• open installation;
• hidden installation;
• waterproof.

An open connection to the network does not imply hiding the pads in the plane of the wall. There are varieties with two and three poles, with protective contact, as well as double or single. Typically, overhead placement is used in rooms with open wiring.

The degree of protection of such devices ranges from IP 20 to IP 23. They are susceptible to moisture and the penetration of small objects into the housing

The hidden connection differs from the previous one by the socket block embedded in the wall or other surface. It is connected to the contacts of hidden wiring.

In terms of protection level, open and hidden products do not differ from each other. And placing them inside a wall does not make them any more dangerous.

The only difference in the graphic representation of hidden rosettes from open ones is a vertical line inside a semicircle, perpendicular to the lower plane

Devices with a waterproof housing are usually installed in places of high humidity. This could be a bathroom, kitchen, or poorly protected areas outside the building.

Their degree of protection ranges from IP44 to IP55. In the first case, this means that objects thicker than 1 mm will not get inside, and the moisture protection is resistance to rain. The second provides protection from dust and safe operation under weak streams of water.

The plastic hinged cover of the protective case protects not only from moisture, but also from dust and small abrasives

Separately, it is worth mentioning the classification by the number of poles.There can be from two to four. In Russia, two-pole sockets with protective contact are mainly used.

All household appliances are powered by this type. Multi-pole, namely with three poles, power industrial equipment: machines, pumps, electric furnaces. They are used in three-phase networks.

Unplug the plug with a smooth movement, holding the protective housing so as not to break the fastenings to the wall. This may cause electric shock

Main types of household switches

When developing a plan for electrifying a room, it is necessary to accurately determine the type of switches. There are a lot of such products on the market of various shapes, purposes and devices.

Principles of product classification

Structurally, the switch is similar to a plug socket. Their components are similar: contacts, block and protective cover. But if the socket is used to connect to the electrical network, then the switch is designed to open this connection by manually acting on the changeover contact.

It opens the only (phase) wire going into it, unlike a socket. And it also closes by pressing the button again. Like sockets, switches have several levels of protection: from IP20 to IP23 and from IP44 to IP55.

On the plan, the switch designation is depicted as an oblique line with a circle at the base and a hook on the opposite side. The number of hooks means the number of keys

To clarify the choice of suitable options, it is enough to systematize them according to several principles.

For example, there is a classification based on the following criteria:

• switching method;
• type of installation;
• by type of switching off and switching on.

In addition, they can be divided according to the principle of operation: one-, two-, three-pole and two-way switches without a zero position.

The depiction of elements on the plan is made using the simplest geometric figures, which have minor and unnoticeable differences at first glance

All variants of symbols, expressed in letter and graphic form, are given here. We advise you to read the useful information.

Switching and installation methods

The option for connecting switches to a live wire can be screw or screwless. In the first case, contact is ensured by pressing the wire against the switch plates with a screw. Over time, this connection can weaken, which leads to heating of the element. Periodically it must be tightened until it is tightly clamped.

In the second case, the phase wire is secured with self-clamping terminals. This makes connecting much easier and faster. The quality of the connection in the terminal is more reliable and does not require further disassembly of the switch to strengthen the contact.

Depending on the placement of the wiring, switches can be built into the wall or overhead. In residential or office premises with hidden wiring, switches are mounted in the wall for the sake of appearance. If the wiring is open, when there are no stylistic requirements for the interior of the room, switching devices are mounted openly on the wall surface.

The European standard requires that switches be installed at a distance of about 10 cm from the door and 90 cm from the floor

Contact closure options

The most common type of household switch is a key switch. The principle of its operation is based on opening and closing the contact by switching the key on which the frame is attached.When switched on, it touches the static contact and completes the electrical circuit. According to the connection diagram, they are of the reversible and cross type.

Pushbutton switches operate in the same way as keypads. In everyday life, they are most often used in table lamps and floor sconces. The button can be locked when turned on or close the circuit only when it is held.

Switches of this type can have one or two buttons. With one or more light control modes

In wall sconces or in technical rooms where the permissible height of electrical equipment does not allow hand reach, products with cords are used. In terms of design, they are basically similar to push-button ones.

Rope switches provide an interesting tactile sensation when turning on the lights. They are much easier to find in the dark by touch.

Rotary types of switches are usually open-mounted. They began to be used more than a hundred years ago, and they only worked in the on/off position and had a very exotic appearance.

Even today, these devices work in ancient buildings and house museums. And recently they have received a second wind and are used in the design of interiors stylized as retro or steampunk, gaining wider functionality.

Goes perfectly with interiors stylized as the eighteenth and nineteenth centuries; in addition, they can serve as a light dimmer

The opposite of the rotary switch is the touch switch. This new technology trend not only received a futuristic design and a fundamentally new control method, but also increased reliability and safety of use.

After all, these semiconductor devices do not have a switching mechanism - electronics are responsible for everything. They are actively used in managing the “smart home” system. The devices are triggered both by pressure and its intensity, by the approach of a palm and even by a voice.

Touch switches equipped with a remote control allow you to control several lighting groups at once and be equipped with many additional functions

Motion sensors in them eliminate the discomfort of entering a dark room by turning on the light automatically, and the temperature sensor allows you to synchronize the switch with the fireplace. The latest models are able to respond to gestures and smoothly change the brightness of the lighting.

Number of poles of switches

According to GOST R 52565-2006, a pole is an element of a switching device that is connected to only one independent part of the circuit. In simple words, a pole completes only one line, such as a light bulb.

There is some confusion regarding the poles of switches and their purpose. To understand, you first need to separate the concepts of an automatic and a conventional light switch in a room.

Automatic switches are equipped with one/four poles, when three phases and a neutral wire are closed. Such switches are installed in the power panels of the room to protect against overloads and short circuits.

If we talk about light switches, then the number of poles means how many lines can be switched on in isolation from each other. For example, several lighting groups in a room can be turned on with one three-key switch. For the same purpose, you can install three single-pole devices, which is less convenient.

Three-key products control combined lighting, groups of light bulbs in a multi-level chandelier, and also serve to turn on individual household appliances

Two-way switches are used when designing complex circuits to control light from several places.

These devices can be with a zero (neutral) position. This is convenient, for example, when lighting long corridors or flights of stairs, when, having turned on the light at the beginning, you can turn it off at the end.

Conclusions and useful video on the topic

Overview of electrical elements using an example of a floor plan:

When installing electrical equipment, craftsmen of any level and direction should not have any misunderstandings with the designer who developed the power supply plan. Therefore, with all the variety of electrical products and methods of its application, graphic symbols on construction drawings and diagrams must have one general form and standard.

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