Connection diagram for boxes in apartments. Installation of electrical sockets, switches and distribution boxes

During installation of electrical wiring or telephone cables. Inside such a device, branches of wires are distributed, directed to different places. They are installed in almost every room, and the main condition is free access for maintenance and repair.

What is a junction box

A distribution or soldered box is an ordinary plastic container with a lid, equipped with holes on the back for wire entry. Such containers are used to ensure uniform and safe distribution of electricity in several rooms. The distribution box involves connecting any lighting fixtures, switches, sockets and other electrical consumers. According to the type of wire cables, distribution containers are made for:

• open wiring that is mounted on top of the wall;
• hidden wiring, which are installed in the wall and plastered.

When the device is installed correctly, the cover is visible and access to the wires is open.

Types of distribution boxes

Electrical distribution boxes are made of plastic, round or rectangular in shape, in different colors (usually black, white or gray). The following types are distinguished:

• soldered box - installed for wiring electrical wires in a room, in order, for example, to power several sockets at once from one cable;
• installation box - used for installing electrical switches and sockets;
• terminal box - installed for redistribution of electricity;
• test adapter box - an ideal device for connecting induction and three-phase electronic meters, short-circuiting the circuit when replacing it, checking the meter;
• mounting box - used for hidden and open wiring for wiring in concrete, brick or plasterboard walls.

There is also a separate distribution box for hidden or external wiring. The price of the product ranges from 12 rubles. per piece up to 530 rub. depending on the type, purpose and material.

Installation of distribution box

The overhead type of device is attached to the wall using dowels. But built-in electrical distribution boxes will require a little work. For installation it is necessary to create a special recess. Usually a niche is made high under the ceiling, a junction box is placed in it, secured with cement or alabaster.

But before direct installation, grooves are made in the wall through which electrical wires will be laid to the box. They are lowered vertically to sockets and switches. In order not to unnecessarily chisel the surfaces, they try to use the gaps between the wall and the floor slabs to install horizontal wiring.

When the grooves are ready, the socket boxes are installed, then they begin laying the electrical wiring, and then the electrical distribution boxes are installed, as mentioned earlier.

Connecting wires in an electrical junction box

Connecting the wires in the junction box can be done in two ways: soldering or special presses. This type of electrical installation work is carried out after the wires and cables have been laid.

So, first of all, you need to disconnect the electrical box, that is, ensure the correct connection of the wires. The ends of the wires placed in the box should be aligned in length by 15-20 centimeters.

If the wires and cables are double insulated, the outer insulation is removed to expose the metal strands. If you are preparing wiring for switching with PPE caps, then it is enough to open the cores by 1-1.5 centimeters. If switching wires involves twisting with further soldering, welding or using sleeves, then for convenience the wires are exposed by 4-5 centimeters.

To make the correct connection the necessary wires, carefully monitor where each wire comes from; To be sure, you can use a very ordinary indicator screwdriver. Next, the wires of switches, lamps or sockets, stripped of insulation, are twisted and the corresponding outgoing ends are found in the junction box.

Connecting socket wires

The main connected elements are sockets, switches, and lamps. Connecting the wires in the distribution box for installing sockets is quite simple: wires of the same color are selected, connected in parallel with each other parallel connection with power supply.

Connecting wires of lighting elements

Connecting the wires of lamps and switches also does not cause any particular difficulties. Since power is supplied to the lighting device through a switch, it is necessary to connect the phase power cable to the input wire of the switch, and connect the one coming from it to the lamp. The other wire of the lighting fixture should be directly connected to the neutral wire of the power supply. As a result, when there is a phase break, the lamp will turn off, ensuring that there is no voltage in the lamp base.

If the switched wires do not fit in the distribution box, there are too many of them, then you can mount a larger device or evenly distribute all the wires into two boxes, powering one from the other.

Telephone junction box

A telephone distribution box in the technical literature is designated by the abbreviation KRT and is intended for the transition of subscriber numbers from a multi-pair cable to individual wires. Conventional boxes are designed for 10 switched telephone pairs, which is indicated in the product model index, although it also happens more(KRTM or KRTO - 10, 20, 30, 50).

There are many modifications that were previously made with a cast iron body, and later - from a lightweight aluminum alloy. Models in a plastic case are marked with the abbreviation KRTP. The first modifications of the boxes were produced under a standard plinth, which later changed in both shape and size.

Purpose of telephone junction boxes

Telephone distribution box KRTM (KRTTO) is used for connecting cables with plastic insulation for subsequent redistribution of telephone pairs into individual cells of subscriber numbers. The metal body can withstand low temperatures, so the device can be installed in unheated rooms. Maximum connection - up to 200 pairs. Additional equipment with locks ensures the reliability of the design, limiting access to the internal contents.

First onto the mounting bracket or clamp distribution box a mortise plinth is installed. Then the input cable cores are inserted through the inlet holes specially provided in the base of the housing. The cores are inserted using a universal tool without the need to strip the insulation.

Standard telephone boxes KRT, KRTP or KRTU are designed for connecting subscriber wiring to a line cable. The KRT-10 distribution box is protected by a molded plastic case and is capable of connecting 10 telephone pairs. Inside, the distribution box has a ten-pair phenolic plinth with tinned contacts that allow repeated soldering.

Design modern models very diverse. In addition, they are produced under different type plinths. For installation of telephone junction boxes in office corridors and staircases apartment buildings Models that can be locked with a key are ideal.

A distribution box is an electrical product within which cable strands are interconnected. Only with its help can you correctly connect a socket, switch or lamp to a power source. It also serves to protect connections from

ingress of dust, moisture, foreign objects and to prevent accidental contact with them.

Boxes come in external (open) and internal (hidden) installation. External ones are designed for connecting cables laid openly: in corrugated cables, metal hoses or plastic cable ducts. To insert the corrugations inside, they are equipped with rubber seals to ensure the required tightness.

IP68 sealing glands for junction box

Boxes used in conjunction with cable ducts do not have clearly marked places for cable entry inside. They are sawn through during installation; in some models, to facilitate this procedure, the body is made thinner in several places.

Boxes for indoor installation walled up in the walls. Hidden wiring cables are installed inside. To insert them inside, places with a thinner body wall are provided, usually round in shape. During installation, the housing is broken into in the right places, cables are inserted inside the box, and the resulting free spaces in the openings between them and the box body are covered with plaster.

All boxes are equipped with removable covers, through which access to the connections is provided. Sometimes inside them there are permanently installed terminal blocks for connecting cable cores.

Choosing a location for installing the box

When installing electrical wiring yourself, you must lay it parallel or perpendicular to the surfaces of the floor and ceiling. The distance from the ceiling to the cables being laid should be 20-30 cm. It is advisable to place boxes feeding a switch or socket above them. This is done so that the box can be easily found. In order not to spoil the design of the premises, they are usually walled up flush with the surface of the walls and then covered with wallpaper. The box that powers the outlet and is located above it, if necessary, will be found faster than one located arbitrarily.

You can install boxes above hanging or stretch ceilings, but then it is necessary to provide access to them for possible subsequent repairs. After all, contact connections are weak point electrical wiring and over time can weaken or even burn out. For repairs, you will need to open the ceiling. This process will lead to unreasonable material costs, and if the installation location of the box is unknown, to very large ones. The same applies to the location of the box hidden in the wall. It should not be covered with a layer of plaster. To open the lid, the maximum that can be done is to cut off the wallpaper opposite it. You can then glue them in place or use a scrap of leftovers that inevitably appear after pasting.

To access boxes located above the suspended ceiling, ventilation hatches are built into its surface.

Box location outdoor installation determined mainly by design and cable length savings. To do this, they are also installed opposite switches, sockets and lamps. But even here you should not install them in hard-to-reach places, so as not to complicate your work.

When installing boxes outdoors with your own hands, you need to choose products with a degree of protection of at least IP44.

IP44 junction box

But to guarantee protection from the penetration of precipitation, it is better to install them under canopies, roofs, and awnings. But the degree of protection of boxes installed outdoors cannot be degraded, even if rain and snow never fall on them. Humid air penetrating inside leads to the formation of condensation, which impairs the insulation between connections or leads to their corrosion. In the first case, a short circuit is possible, in the second - oxidation and contact failure.

Installation of distribution box

Installation of junction boxes in walls can be done in different ways, depending on the availability of the tool. The optimal and least labor-intensive option is to use a hammer drill attachment called a crown.

It is a ring with pobedite or diamond cutting edges, in the center of which a concrete drill is located. The drill performs the functions of centering the crown, and it itself cuts out a round segment from the wall.

An example of a diamond-coated concrete bit that can be used to drill holes for distribution boxes

After drilling to the required depth, the segment is removed with a hammer and chisel or a mounting blade mounted on a hammer drill.

There are crowns of various diameters to suit any size of junction box

Holes can also be made with the mounting blade itself, especially for rectangular or large boxes. First, you need to drill holes along the edges of the required opening using a concrete drill. The section of wall between the holes is cut out using a spatula and a hammer drill set to the hammer mode, or with a hammer and chisel. Instead of a chisel, you can use a wide flat-head screwdriver with a strong handle. Installation of holes in the walls of a panel house is carried out only with a hammer drill; other methods will not bring results. At the same time, holes for sockets and switches are installed.

Then grooves are laid, cables are laid in them, the ends of which are inserted into boxes so that the ends 10-15 cm long stick out from them. It is better to cut the cables in the boxes in advance. The cables must enter the box itself uncut, more than a centimeter long. If the box is small, the length of the uncut cable in it must be minimized, otherwise the wires will not fit into it later. If, when sealing grooves, there is a possibility of cables shifting along the length, then it is better to cut them in connection boxes, as well as in installation boxes for a socket or switch, after finishing the plastering work.

Installation of cables in the junction box

After the plaster has hardened, you can electrical connections. To correctly connect sockets and switches in boxes with your own hands, you need to follow the action plan described below.

1. Place the cut cable cores to the sides, grouping them according to their purpose. First, it is better to decide on the protective conductors (PE). In cables they are yellow-green. Collect into one bundle the PE conductors going to the lamp housings, to the sockets, from the power source and to the next box. Be careful: the yellow-green wire going to the switch does not belong to this connection. It is important to remember: even if you do not plan to install an outlet with a grounding contact, a three-core cable must go to it, and its PE conductor must be connected in the box or panel. This is done so that in the future it will be possible in place of a regular outlet.
2. To prevent the bun from falling apart, tie it together with a tie or tape. Connecting the wires can be done right away, but it is better to complete the planning process completely, since you will need to untangle the remaining wires.
3. Collect all zero working conductors into a bundle. They are blue in color and are assembled from supply and outgoing cables, as well as those supplying the outlet. An exception also applies to cables to switches.
4. Then we collect together the phase conductors of the incoming and outgoing cable lines, sockets and add to them one conductor from the cables going to the switches. The color of these conductors may be white, black or other, but not yellow-green or blue. From the switch cable we take a conductor of the same color as the phase conductors.
5. We are putting together a diagram for connecting lamps. To do this, we take blue or yellow-green wires from the switches and connect them to the remaining unassigned phase conductors of the lamps. This case is an exception to the rule, when yellow-green or blue wires can be used to connect a phase, that is, not for their intended purpose.
6. We connect grouped cores using one of the following methods: welding, soldering, installation of terminals.
7. We isolate the connections.
8. We put the wires in the box.

Electrical wiring installation in a house, apartment, garage, office, etc. is always performed with the installation of distribution (branch) boxes. At least one is always installed in each room.

Branch boxes diverge electrical cables or wires to lamps, switches and sockets. They consist of a plastic case with a lid; they can be built-in for hidden electrical wiring(in Figures 3 and 4) and overhead - for external (in Figures 1 and 2).

Metal distribution boxes are subject to mandatory grounding and are installed only when laying electrical cables in metal pipes. For example, in wooden houses and buildings in accordance with the rules and requirements.

Branch boxes vary in size and shape. Large boxes should be used in places where there will be a large number of cables or wires. It is better to take round ones in shape than square or rectangular ones, because you won’t need to level them. And you can use a hole saw to drill a hole in drywall, block, brick, etc.

Before you start installing the box it is necessary to make grooves and secure cables in them from the installation site to sockets, switches and lamps. Or secure the cables behind the drywall or panels that line the walls or ceiling.

With open wiring the overhead box is attached to the ceiling or wall with 2 screws or dowels; just route the electrical cables through special seals. It is necessary to cut a hole in the seals slightly smaller than the diameter of the cable. The illustration shows an option with dust seals. There are waterproof options with rubber seals and threaded plugs.

For installation of a built-in box it is necessary to knock out or drill a recess into which the box must then be pressed flush. It is much easier to place the box in drywall.

Installing a distribution box in drywall.

After this, we strip the wires and connect them along this line.

How to install a distribution box for hidden electrical wiring.

All electrical wiring in houses and apartments is hidden under plaster or in channels panel houses, so the junction box is hidden flush with the wall. For her installation required:

Not round when applied the box must be ensured that it is fixed exactly level. This is especially true for rectangular options. Square boxes, even if crooked, in most cases allow you to straighten the lid.

Reading time ≈ 4 minutes

One of important stages Electrical wiring is the connection of wires in the electrical junction box, which follows immediately after laying the cable. At first glance, some may think that using a junction box to connect wires is essentially a waste of time, but this assumption is wrong for several reasons.

Wire connection diagram in the junction box

During operation of the electrical wiring, malfunctions may occur - for example, a circuit break has occurred. If during electrical installation the workers did without a distribution box, and the connections were simply rolled up finishing material type of plaster, then in order to get to the connections again, you will have to disturb the external finish - tear off the wallpaper, break the layer of plaster, etc. It is unlikely that anyone will be satisfied with such prospects. If in the future you need to install additional sockets, then in such cases it is not always convenient to pull wires from previously installed sockets; it is easier to organize the connection directly to the box.

If the wires are connected using terminal blocks, then you will have to drill a fairly deep channel into the wall, which is much more labor-intensive than simply connecting the wires in a junction box.

Finally, from a fire safety point of view, the advantage of using junction boxes is undeniable. For the correct organization of electrical installation work, there are special Rules for the Construction of Electrical Installations (PUE), which also regulate the procedure for connecting electrical wires.

Methods for connecting wires in a junction box

According to these rules (PUE), there are the following methods for connecting wires in a junction box:

• Connection using terminal blocks is the most preferred method: the terminal blocks are small in size and can easily fit into the distribution box, and it is not difficult to buy them. All that remains is to cut the wires to a certain length, connect the corresponding wires and place the resulting assembly in the box.
• Connecting wires in a junction box soldering method- a method more suitable for professionals who have sufficient experience in carrying out such a procedure. Without experience, a person will spend a lot of time on soldering, and it is not a fact that the result will be a high-quality connection.
• Connecting wires in the distribution box crimping method can be considered the most reliable permanent connection. However, this is quite labor-intensive work that requires skills, special devices and materials - these are press jaws, copper or aluminum sleeves and heat-shrinkable tubing. Pre-stripped cores should be inserted at both ends of the sleeve until they stop and the connection should be crimped. Immediately before crimping, a heat-shrink tube should be put on one of the switched wires, and after crimping, slide the tube onto the sleeve and heat it to the shrinkage temperature.

The twisting method is the most simple option connections. However, if we talk about whether such a connection of wires in a junction box is reliable, PUEs allow such a method only as a temporary one and prohibit twisting without subsequent full modification of the connection.

For those who are faced with such a task as connecting wires in a junction box for the first time, the photos and videos presented in the article will help to visualize as clearly as possible how this procedure is carried out in all the ways listed above.

The main wiring elements switched in the box are lamps and sockets, and the wire connection diagram in the distribution box will be different for them. The socket will require a simple connection of wires by color. There will be three colors in total: phase (gray, brown or black), zero (blue or cyan), ground (yellow with a green stripe). There are also wires without grounding, then the cable will be two-core, and instead of three colors there will be two. For a lamp with a single-key switch, only 2 wires will need to be connected in the box: the zero will be connected to the wire going directly to the lamp, and the phase will pass to the lamp through the switch. For a chandelier with a 2-key switch, the only difference will be that in this case, 2 wires will go to the chandelier from the switch, responsible for different groups of light bulbs, and the zero will remain common.

Video of connecting wires in a junction box

When repairing electrical wiring yourself, you should pay attention special attention connecting wires in junction boxes, because electrical engineering, as electricians say, is the science of contacts, both desirable, ensuring an uninterrupted supply of electricity, and unacceptable, due to which many accidents occur.

This article, with the help of links to other materials of this resource, will present all the minimum knowledge and skills required home handyman for successful electrical installation, and the entire process of connecting wires in the junction box will be described step by step, starting from preparatory stages, ending with the introduction of the installed home network into operation.

The scheme is the most important stage

For an experienced electrician, it will not be difficult to connect a switch and a light bulb without a drawing, making a connection of wires in a junction box, guided by the color marking of the cable cores or by the results of testing already installed wiring.

But experienced craftsmen succeed in such work only because connection diagram clearly imprinted in the mind thanks to many years of practice.

Simple scheme connections of wires in the junction box when connecting a switch and a light bulb

If a master needs to carry out electrical wiring at any facility, then he will begin first by designing a circuit, if other specialists have not done this before him. Of course, there are standards, GOST and SNiP, according to which all electrical wiring drawings are made, but for an apartment or private house, a hand-drawn diagram is suitable, the main thing is that it subsequently works properly and safely.

This approach not only protects against errors, but also allows you to save time by dividing labor - when carrying out electrical installation in a junction box, the electrician will not be distracted by drawing up a wiring plan, while simultaneously trying to keep the planned lines and connections in his head.

More complex circuit connecting a two-button switch

Examples of schemes for and apartments can be viewed by following the links. You will also need to familiarize yourself with the symbolic graphic symbols of the network elements so that you can consult with a familiar mechanic by showing him the diagram, or in the future carry out electrical wiring repairs by checking the saved drawing.

The importance of planning electrical wiring is also determined by rationality and efficiency. When drawing up a wiring diagram, you need to draw up a plan in such a way that there are as few junction boxes in the apartment as possible, because each connection of wires increases the risk of losing contact.

Example of a hand-drawn wiring diagram (blue circles indicate junction boxes)

When connecting one socket or switch, many electricians advise doing without a distribution box altogether and connecting the wires in the socket box. This decision is determined by the reluctance of apartment owners to provide access to the distribution box, as required by the PUE (in their opinion, the interior of the home is deteriorating). The socket or switch can be easily disassembled, which provides access to the connection of wires in the socket box.

Quote from PUE

A detailed story about the various wiring diagrams in junction boxes is shown in the video:

Correct pin markings

In order to connect the wires in the junction box according to the diagram without undue doubt, it is necessary that the terminals of the laid electrical wiring be marked. Very often, disconnection (dividing the main electrical wiring line into several branches) is made when all the wires have already been laid and hidden under the plaster, and there will be no way to visually trace the purpose of the cables.

It's easy to get confused without being sure of the purpose of the same cables

In order not to waste time on cables, which is also described on this site, you need to mark their ends at the stage of laying the cables. In some cases, if there are few wires in the distribution box, you can be guided by the color of the insulation of the current-carrying conductors. But with a large accumulation of cables, the colors of the wire insulation will be repeated, so the likelihood of error increases.

To eliminate the possibility of incorrect connection, you must label termination of laid cables by any in an accessible way. The industry produces many different tags designed to mark terminals. Very often, electricians use transparent heat-shrinkable tubing by inserting a strip of paper with a terminal symbol inside.

Samples of industrially produced cable marking tags

You can also use transparent tape to wrap it around tags with inscriptions. As a last resort, use a marker or felt-tip pen to write the designations directly on the wire insulation or on the wall - but there is a risk that the inscriptions will be erased during the installation process.

Electrical wiring terminals are marked on the wall

You should also strictly adhere to the color marking of the cables (brown, red, black - phase, blue - working zero, green with yellow stripes - protective conductor PE).

Generally accepted color coding cable core insulation

Installation of distribution box

Before starting electrical installation, you need to make sure that the junction box is securely fixed. , which depend on the type of wiring, are also described on this site. The importance of fixation is determined by the possibility of damage to already connected wires when manipulating the junction box and cables.

When working with single-core wires, frequent bending of the current-carrying wires should be avoided. Stranded wires Although they allow frequent bends, mechanical loads and the weight of a loose cable of hanging electrical wiring can damage the finished connection, so it is important not to violate electrical installation technology.

PUE requirement for fixing cables and boxes

If installed hidden wiring in brick or concrete wall, then the wires are laid in a groove, made manually or with the help of tools (grooving), and socket boxes and distribution boxes are mounted in holes that are drilled in the wall using a special crown. Fixation is carried out using plaster or alabaster.

Box bit for drilling holes for distribution boxes

Each type of wire connection requires a certain length of leads. For example, when using very bulky connecting blocks that have bolted connection terminals, craftsmen try to leave as little free length of wires as possible so that all connections fit into the box.

But, if welding of wires is used, then the length of the bare conductors should be about seven centimeters to prevent the insulation from melting during strong heating, plus the length of the insulated conductors for convenient and safe installation. Long exposed connected wires are insulated and laid in a junction box.

Wire connections are made by welding

The above examples mean that, regardless of the chosen method of connecting the wires, the length of the leads protruding from the junction box must be at least ten centimeters, because excess conductors can always be cut off, but it will be extremely difficult to extend them, and the reliability of the entire electrical wiring line will deteriorate. .

Conductor training

On at this stage the master must finally decide how to connect the wires in the junction box, and accordingly prepare guides– remove the insulation and bend the cable cores. A list of existing types of wire connections is given below, and now, regardless of the chosen method, special attention should be paid to the quality of stripping and preparation of conductors for electrical installation.

Stripped wires are ready for connection in the junction box

To carry out any electrical installation, the master must have, which you can familiarize yourself with by clicking on the link. At this stage, the wires are prepared for connection - stripping of insulation. Particular care should be taken in this process, since when using improvised means (knife, pliers, wire cutters), invisible damage to the current-carrying wires is possible.

Professional electrician's tool kit

When bending wires and subsequent installation, barely noticeable cracks in the metal can increase, which will worsen electrical conductivity and can lead to breakage and loss of contact. At high currents, a large amount of heat will be released in the thinnest section of the circuit (at the crack site), which can heat the insulation and even the metal of the conductor itself to the melting point.

With a large current in a broken conductor, an avalanche-like process occurs - when heated, the resistance of the material increases, which further increases the heat release. This process ends with the melting of the conductor metal and the appearance of an electric arc, which, burning other wire connections in the junction box, renders them completely unusable.

Photo of an electric arc burning in a junction box

Without a doubt, a true master even with the help kitchen knife will be able to carefully and quickly remove the insulation without damaging the current-carrying conductor. But for people without experience it will be very difficult to avoid subtle damage to the material of the conductors, therefore, in order for the connection of wires in the junction box to be of high quality, it is necessary to use special ones (strippers).

Variety of stripping tools

Many people have seen the picture that some craftsmen remove insulation with the help of teeth. There is absolutely no need to follow this example, in which case purchasing a professional insulation stripping tool will cost less than the services of a dentist.

An overview of various stripping tools is shown in the video:

Wire connection methods

As already mentioned, for in various ways Connecting wires to a junction box has its own electrical installation technology, which consists of the length of stripped conductors, their bending and the use of appropriate tools.

Since each of possible ways has many specific nuances and requires the use of special tools and skills; below, in the form of a list with links, the types of wire connections are presented:

• Terminal blocks;
• PPE caps;
• Connecting sleeves;
• Welding of conductors.

Wiring in a junction box using terminal blocks

Each of the above methods has its own advantages and disadvantages, which you must familiarize yourself with by studying the materials and following the links provided. You should choose the type of connections for doing electrical installation yourself based on the availability of tools, skills, the ability to purchase materials and the expected quality of contacts.

Most reliable welding of wires is considered, but it requires special welding machine and specific skills. Soldering of conductors, which also has good characteristics, requires soldering iron skills. Wago terminal blocks are quite easy to install, reliable if the products are correctly selected according to the load, and allow the connection of multi-core wires without the use of special lugs, but you should be wary of counterfeits.

Connections in the junction box are made using Wago terminal blocks

The use of sleeves is reliable; when using special products, it is possible to connect copper and aluminum, but the connection itself requires special pliers and is non-separable, which does not give a chance for easy correction of electrical installation errors. PPE caps are reliable if the technology is followed and the diameter is selected correctly. Terminal blocks require bolted connections to be securely tightened.

PPE caps in distribution box

It should be remembered that according to the PUE, twisting of wires is not allowed in its pure form

Twisting in its pure form is not included in the list of permitted connections

Testing wire connections in junction boxes

After all connections have been made, the exposed sections of the conductors are insulated using heat-shrinkable tubing, and the wires are laid in junction boxes. The boxes themselves are left open until the installed electrical wiring is tested. First, voltage is supplied to the connected lines by turning on the corresponding circuit breakers.

Insulating connections in the junction box using heat shrink tubing

If, after switching on, nothing sparked anywhere and the machine was not knocked out due to a short circuit due to an erroneous connection of wires or poor-quality insulation of connections, carry out tests electrical wiring with load current (loading), which is carried out by connecting various electrical appliances to mounted lines. It is recommended to load each line with the maximum permissible current.

The download should continue for some time (preferably several hours). During this period, possible electrical installation defects will have time to manifest themselves. A visual inspection of the connections in the junction boxes should be carried out - signs of high temperature will be visible by melting of the insulation or terminal blocks. It is also important that there is no characteristic odor of overheated or burnt insulation.

Melted insulation of one of the connections in the junction box

After relieving the voltage, you should check all connections by touch - they should not be hot. If, when loading the electrical wiring with the maximum rated current for several hours, no comments are identified regarding the operation of the connections, then the electrical installation is considered normal, the junction boxes can be closed and the wiring can be put into operation.