Junction box for outdoor and flush wiring: types, classification + installation instructions

How to install a junction box

Today, Electric Raccoon will tell you about several ways to install a junction box in concrete. The electrical box is made of metal or plastic in the form of a small container.Inside this container, during installation work in the room, all groups of conductors are connected.

The main purpose of the junction box:

Possibility of maintenance and access to the repair of the home electrical network. In the event of failure of the room wiring, together with the socket group, it is possible to eliminate all problems without any problems.

Availability of connecting new lines to room wiring. This refers to the possibility of installing sockets, if additional ones are needed. This eliminates the need to pull new cables from the main shield - it will be enough just to create an additional route from the junction box.

It is possible to ensure a uniform distribution of electrical energy throughout the room by creating additional directions of the power grid and connecting them into one.

From the foregoing, we can conclude that a properly installed junction box plays an important role in the installation of electrical wiring both in the house and in any other room.

Insulators for outdoor wiring

When laying open electrical wiring, insulators are used to fasten the wires. These insulators perform a simple function - they are the base on which the electrical wire is attached. Both ceramic and plastic insulators are commercially available.

For open wiring equipment in retro-style rooms, ceramic insulators are used as a design element. In this case, special multi-colored ceramic insulators are used.

Ceramic insulators are made of high quality material and have high performance characteristics:

• have high hardness and strength;
• resistant to changes in temperature and humidity;
• have high dielectric characteristics;
• have a long service life.

When installing open wiring on insulators, the following requirements must be met:

• from the edge of the socket, switch or junction box, the insulator should be at a distance of about 4 cm;
• with a horizontal arrangement of wires, there must be at least 5 insulators per meter of wiring. With a vertical arrangement of wires, this distance may be somewhat greater;
• when turning the wire, use 2 insulators located at an angle of 45 degrees.

How to install a corrugated fence? You will find out the answer to this question by reading this article.

And here is an article about brick fences.

Is it possible to do without junction boxes at all?

Theoretically, yes. But for this you will need to connect the switchboard and each place of electricity consumption in the apartment with a separate wire. This will lead to a large consumption of electrical wiring and the need to make wide and deep strobes. to be able to lay several rows of wire in them.

Ultimately, the disadvantages of this method will greatly outweigh the disadvantages of using junction boxes. Savings due to the elimination of the latter will be repeatedly depreciated by the increased costs of electrical wiring.

As an argument against the use of junction boxes, you can sometimes hear this; although laying a separate line to each consumption point loses economically to the variant with junction boxes, but it is safer, since it eliminates the connection of wires at nodal points.

There is only one answer to this. A correct, professionally made connection of wires in a junction box is absolutely safe.While everyone is entitled to their own point of view, the option with the use of junction boxes is still more preferable than without them.

The main function of the junction box

With the help of this electrical product, you can significantly reduce the cost of organizing electrical wiring. Without this element, each electrical appliance would have to be connected to a separate cable, which would lead to an increase in the number of channels required for installation and ruin the appearance.

Proper distribution of the cable inside the box will increase the safety of residential and non-residential rooms. This is due to the insulation of connection points with combustible materials contained in the wall. The design of the equipment is thought out to the smallest detail, therefore, it guarantees the ease of repair work.

But the main function of the box is related to the uniform distribution of electrical energy between all consumers installed in the room. In addition, the structure of the product takes into account the potential expansion due to the addition of new branches of the electrical circuit.

Methods for connecting wires in junction boxes

Getting the wires inside the box is half the battle. Now you need to choose a reliable and easy-to-maintain connection.

All cable line connections are divided into two main categories:

• Detachable, that is, the wiring can be repeatedly disconnected and connected back, without critical damage to the wire or connecting device. For example - a screw connection on the contact blocks.
• One-piece, that is, when the conductors are separated. the connection is broken. This is not a big problem, it's just that the cable is shortened each time, and the connecting devices have to be bought again.

The type of splicing when disconnecting the boxes is selected based on the design of the overall network. If it is planned to periodically disconnect one or two branches from a common box, it is better to choose a screw connection, or reusable quick-release terminals.

For permanent connections that will not be unmounted for many years, the same terminals are used, only for one-time use. Despite the obvious disadvantage: the impossibility of reuse, such terminals provide more reliable contact, compared to reusable ones.

If you use only copper conductor in both the backbone network and subscriber branches, there are cheaper ways to permanently connect the wires:

1. Twisting with welding. Creates a reliable contact, without the danger of sparking and heating of the wiring under heavy load.
   The connection is simple, but requires special equipment. As a last resort. you can melt the copper tips with a portable gas burner.
2. Solder twist. Not as reliable as with reflow tips, but when using refractory solders, the connection practically does not lose strength, even when heated.
   The advantage is availability. A powerful soldering iron is easier to find than welding equipment. The basic rule: strength is provided by twisting, solder simply fills the voids, improving contact.
3. Twisting with mechanical fixation (crimping). Doubtful method, since there is a possibility of damage to current-carrying wires.
4. There is nothing to say about ordinary twisting: although it is not prohibited, this technique is practically not used.

Direct connection (disconnection)

Is it possible to arrange electrical wiring without junction boxes? With a branching of no more than 2 lines - easily. Several conditions must be met:

• If the connection is made by twisting, soldering with refractory solder is required. You can apply compression.
• "T" shaped connections are undesirable, it is better to perform a "Y" shaped branching.
• After connecting and checking for contact quality, the joint must be carefully insulated and protected from moisture. Especially if the connection is carried out in hidden wiring (plaster wall), or on the street.

Junction box installation

Installation of metal junction boxes provides only external installation of such products.

Therefore, the instruction in this case is simple:

1. Bring tubular channels with wire to the entry points.
2. Fix the pipes to the walls of the housing and bring the ends of the cable into its inner area.

Fixing the body of the product to the wall is carried out with screws through the holes designed for this. Then connect the cables according to the scheme, close the box and fix the cover with screws.

Important! When working with wiring, you must remember that you need to de-energize the entire room completely, otherwise, from the contact of screwdrivers and wires, you can get an electric shock or cause a short circuit. To check the voltage in the network, use indicator screwdrivers or a multimeter. These two tools should be in every home.

These two tools should be in every home.

To check the voltage in the network, use indicator screwdrivers or a multimeter. These two tools should be in every home.

Experts advise using electric metal junction boxes in any room.It's cheaper than plugging a socket into every wire, and it's also much safer. It is not recommended to install it yourself without special indicator screwdrivers and knowledge. Any intervention in the wiring threatens short circuit.

*Prices in the article are for April 2020.

outdoor products

If the first two types were only suitable for indoor installation, then the third option is suitable for those who decide to install the box outdoors. Mounting the box outdoors implies exposure to natural factors such as rain, fog, freezing, etc. Since all these factors have in common that they create moisture that can conduct electricity, outdoor types of boxes must be airtight. To do this, a special rubber seal is laid between the lid and the body, which prevents water from entering inside. In this case, the wires are inserted inside with the help of crimp (collet) clamps.

However, it is worth adding here that the estimate for the installation of junction boxes will be more expensive than for the installation of conventional ones, if the installation is done by specialists.

Features of wiring installation

All electrical work is carried out only after the installation of the electrical panel and the meter. After that, the places of switching equipment are determined. In order to properly lay the wires and install the socket boxes, a survey of the cable route, the conditions for laying the wiring and electrical products is carried out.

The accuracy of electrification performance guarantees not only an aesthetic appearance, but also the safety of the entire home. So, when installing a socket box as a junction box, you must follow the installation rules, these are:

1. Fix the socket box in a wall made of brick, concrete, drywall using a building mixture.
2. Install the socket flush with the wall surface with closed wiring.
3. To fasten the glass, use special clamping screws with plates.

When laying the cable, you should use special fasteners that will protect it from mechanical damage and become a ground. When designing an electrical network through sockets and switches, it is necessary to use only high-quality equipment.

Recently, installation sockets with a more in-depth shape have become in great demand, so that the supply of wires formed by loops or folds fits compactly without sharp creases.

Wiring without junction box

The wiring architecture is compiled taking into account the interests and wishes of the owner of the property. Wiring is a series connection of the circuit without junction boxes. The conductors are connected to the electrical system in turn one after another and are fed from each lighting point, socket, switch immediately to the switchboard.

Before starting work, a preliminary calculation of the estimated amount of current consumption when using the planned electrical appliances and devices is carried out. The connection diagram includes the necessary set of wires and cables, installation of sockets, switches, electrical appliances.

New wiring requirements consider the use of copper conductors only. Contact connections of wires during electrical installation play an important role in any electrical system. They must be resistant to mechanical damage, safe.

Distribution box types

Distribution boxes are divided according to the following characteristics:

• composition and raw materials used. Basically, the boxes are made of metal using PVC;
• by appearance: oval, square, round;
• according to the level of protection of the cover IP (without protection, with protection, sealed);
• according to the method of entering the wire into the box. Also, the walls can be smooth with or without holes;
• according to the closing method: with adjustable lid, regular lid;
• installation method can be hidden or open.

Types of products by size

Note! There is some confusion in the naming of the wiring boxes. The junction box is sometimes understood as a socket, so people do not see the difference, but they are different things.

Overhead

This type of box is installed on the wall. The product for hiding cables is practical in that you can quickly find the point where the wires connect if necessary.

Surface type IP42

This installation method is used in industrial plants and offices, that is, in those places where there are a large number of consumers of electrical energy. In private houses, the junction box can be mounted in the utility room.

Internal

Hidden wiring is installed in residential premises, while the wires are laid in special cable channels and hidden behind plaster. Such a junction box is mounted in a pre-prepared trench in the wall, and strobes for the cable go from it. In this case, it can be installed both in a solid brick or concrete wall, and in drywall.

With hidden wiring, the cables are hidden in the wall

Overview of models on the market

Junction box Tuso

Characteristics:

• diameter 60 mm, depth 40 mm;
• mounting, or branching;
• round shape, consisting of a body and a cover;
• body and cover material - non-combustible plastic;
• fixing the lid on the latches in the lid and the body;
• it is applied to installation in concrete and brick walls;
• fastening in an open form on screws or self-tapping screws is possible;
• number of inputs - 4 with rubber seals;
• moisture protection class -;

Price - from 20.00 to 35.00 rubles per piece.

Junction box Legrand Atlantic IK10

Characteristics:

• dimensions 150*150*80 mm;
• rectangular shape for indoor installation,
• metal;
• fixing the cover with screws into the case;
• it is applied to installation in concrete and brick walls;
• fastening through the case or on brackets is possible;
• supplied with perforated mounting rails;
• moisture protection class - IP66;
• internal and external paintwork - textured coating color RAL 7035;

Price - from 3173.00 to 3300.00 rubles per piece.

Classification of electrical wiring boxes

Outdoor junction boxes are divided according to several criteria.

Production material:

• Polymer - polyethylene, polypropylene, polystyrene cases.
• Metal - made of tin or aluminum and its alloys.

Purpose:

• Household - for breeding electrical wiring, where single-phase networks are used.
• Industrial - high-strength mini-boxes, where three-phase voltage wires are bred.
• Special - junction boxes for outdoor installation for breeding signal cables of pulse, radio frequency and microwave equipment.

Installation method:

• Open type - wiring runs outside the surface.
• Hidden type - the cables are hidden inside the strobe.

Security level:

• IP44 - boxes that can be used outdoors under cover from direct rain, dust, in rooms with a humid environment.
• IP55 - boxes that can withstand a short direct hit of water and do not let dust through. The most popular type of distribution equipment.
• IP65 - designed for installation in places highly exposed to the atmosphere, do not let rain water and dust through.
• IP67 - can be kept in a humid environment for a long time, for example, underground or on its surface.
• IP68 - able to protect wiring under water. They are designed for shallow depths.

Mounting technology

Installation of junction boxes is carried out according to the following scheme:

• Creation of a network of wires intended for laying cables from electrical installation products.
• Lines to switches and sockets are laid strictly vertically, and horizontal ones can be placed in niches formed by floor slabs or a wall.
• Fixing the junction box in the prepared hole with dowels or self-tapping screws and fixing it with plaster or alabaster (similar to the installation of socket boxes in a hidden way).
• Performing switching and connecting wires using terminals or by soldering.
• Insulated cables are neatly laid and closed, while providing for the possibility of unhindered access.

Junction box installation technology

So, let's talk directly about the process of installing and connecting the distribution junction box. If we talk about the installation of the box itself, there is nothing complicated or problematic here. Embedded options for boxes are embedded in the walls, and overheads are attached to the walls with dowels or self-tapping screws.The installation of the built-in box is more complex and time-consuming, in this case it implies the creation of a special landing niche. In one of the walls, closer to the ceiling, it is necessary to make a niche of the appropriate size, it is there that the box will be installed and fixed with alabaster or cement mortar.

However, these procedures refer to the final stage of work. First of all, you should start creating a "network" of gates - channels through which cables will be connected to the junction box. The required number of descents to the switch boxes and sockets must have a strictly vertical position. In order to carry out horizontal cable laying, it is recommended to use the gaps between the floor slabs and the walls.

After finishing the preparation of the strobe and installing the socket boxes, we proceed directly to the electrical wiring device - an important part of this process will be the installation and connection of the junction box. Often the process of connecting wires inside the junction box causes certain difficulties.

In order to avoid them, we recommend marking each end of the cable in one way or another. For example, we bring the wire that supplies power from the electrical panel - we mark it with the appropriate word, we bring the cable from the socket block - the same, etc. Each individual electrical circuit that we connect to the junction box must be signed accordingly, in which case we will not be confused later

Often the process of connecting wires inside the junction box causes certain difficulties. In order to avoid them, we recommend marking each end of the cable in one way or another.For example, we bring the wire that supplies power from the electrical panel - we mark it with the appropriate word, we bring the cable from the socket block - the same, etc. Each individual electrical circuit that we connect to the junction box must be signed accordingly, in which case we will not be confused later.

Cable cross section

Now, for a couple of minutes, let's digress from the junction box and say a few words about the cable sections that are used when wiring a house or apartment. It is known that the supply of voltage to the premises from the electrical panel, as a rule, is carried out using a three or two-core cable with a cross section of at least 4 square millimeters. This section allows the cable to withstand any powerful energy consumers without any problems. To connect sockets, cables with a cross section of 2.5 square millimeters are used, and for a lighting system, a cross section of one and a half squares is sufficient.

Connection principles

Connecting conductors in a junction box with caps

To avoid confusion, each wire has a different color for a quick connection. The following combination of colors is considered the most popular: light green, green - grounding, blue - zero, white or yellow color symbolizes the phase

When connecting the device, it is important to strictly follow the sequence

For the correct connection of wires in the junction box, you must first draw up a project. It is required to determine the exact location of the points of electricity intake. Distribution devices in accordance with the scheme are installed in the most suitable and convenient places.

Distribution box device

Terminal Junction Box

According to its purpose, the body of the device must have a small weight and dimensions, as well as provide high-quality insulation of the wiring connecting points. Distribution boxes can have a rectangular, square or round body, which has holes for laying electrical circuits.

Devices intended for outdoor installation have the following types of wall mounting:

• They can be installed on special tension lines, as well as equipped with special fasteners on a cable.
• The case is equipped with internal holes for secure fixation.
• The presence of external holes.

Distribution devices are also divided according to the material of manufacture and dimensions. Experts recommend giving preference to plastic cases.

Wire connection methods

As already mentioned, for various methods of connecting wires to a junction box, there is its own wiring technology, which consists in the length of the stripped conductors, their bending and the use of appropriate tools.

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

• Terminal blocks;
• Terminal blocks Wago;
• PPE caps;
• Connecting sleeves;
• Soldering wires;
• Conductor welding.

Wiring wires in a junction box using terminal blocks Each of the above methods has its advantages and disadvantages, which you must familiarize yourself with by studying the materials by clicking on the links provided.Choosing the type of connections for do-it-yourself wiring should be based on the availability of tools, skills, the possibility of acquiring materials and the expected quality of contacts.

Wire welding is considered the most reliable, but it requires a special welding machine and specific skills. Soldering conductors, which also has good characteristics, requires soldering iron skills. Wago terminal blocks are quite easy to install, reliable with properly selected products according to the load, allow the connection of stranded wires without the use of special lugs, but you should beware of fakes.

Connections in the junction box are made using Wago terminal blocks

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

PPE caps in the junction box

Twisting in its pure form is not included in the list of connections allowed by PUE

Testing wire connections in junction boxes

After all connections are made, the exposed sections of the conductors are insulated with heat shrink tubing, and the wires are laid in junction boxes. The boxes themselves are left open until testing of the installed wiring. First, the connected lines are energized by turning on the appropriate circuit breakers.

Insulation of connections in the junction box with heat shrink tubing

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

The download should take some time (preferably several hours). During this period, possible defects in electrical installation will have time to manifest themselves. A visual inspection of the connections in the junction boxes should be made - signs of high temperature will be visible by melting the insulation or terminal blocks

It is also important that there is no characteristic smell of overheated or burnt insulation.

Melted insulation of one of the connections in the junction box

After removing the voltage, check all connections by touch - they should not be hot. If, when loading the wiring with the maximum rated current for several hours, no remarks were found regarding the operation of the connections, then the wiring is considered normal, the junction boxes can be closed and the wiring can be put into operation.

Classification

Boxes can be installed open and hidden. Which one to choose depends on the personal preferences of the owner of the premises. Each type is described in detail below.

Mounting process

For concealed wiring

Hidden-type junction boxes have the same technical properties as outdoor-type boxes. They are also made from plastic and polystyrene.Moreover, plastic is mainly used for the production of the body, and covers are made of polystyrene.

For thick concrete walls, soldering shields are produced with a protection level of IP20-IP30. In appearance, they can be round or square, the color is from white to blue, the cover is always in light colors.

For open wiring

For open-type wiring, round shields are mainly installed. The material used is plastic of the same color.

For open wiring, the AP9 model is excellent, which is installed in places of high humidity (bathroom). The body of the box is made on the basis of two-component casting.

Size range

On the inside of the lid there is a special compartment around the entire perimeter. There you can lay a seal if the box is installed in the bathroom.

Note! The lid is mounted on a flexible spring, which is convenient during use.

The product protection level is IP 55.

Methods for connecting wires in a junction box

There are several basic ways to connect wiring in a junction box. In order to choose one of them, you need to consider the options in more detail.

Twisting and insulation

This is an old, but at the same time, a method of wiring connection that has been proven over the years. The bottom line is that the ends of the conductors are first stripped from the insulation layer, and then twisted together with pliers. After that, this place is wrapped with electrical tape.

This method has advantages:

• ease of installation;
• no need for additional expenses.

However, there are also some disadvantages:

• poor-quality connection of cores;
• the inability to connect copper and aluminum wires.

It is worth noting that in this way the conductors are often connected during temporary installation of electrical wiring.According to safety regulations, the connection method is not suitable for rooms with a high level of humidity.

Soldering or welding

It is in these ways that it will be possible to make a durable connection of the wiring cores. First, their ends are carefully cleaned from the insulating layer, then twisted, but without effort. Next, you will need to solder the wires with the help of solder and a soldering iron so that they turn out to be monolithic. Then you need to wait until they cool down naturally, and only then wrap them with electrical tape.

In cases of soldering thick wires, you will need to use a soldering iron with a dense copper tip.

The advantage of soldering is the reliability of the connections, but this method also has some disadvantages:

• the need to purchase a soldering iron;
• this is a laborious process that not every beginner can handle;
• the connection is non-separable;
• over time, the level of resistance in the solder increases, which leads to voltage leakage.

Often, instead of soldering, the cores are connected by welding. The process has a similar principle, only a welding machine is already used here, so the master must have the appropriate skills.

Crimping with sleeves

This is also one of the most reliable methods of fixing conductor cores. Here they are placed in a special sleeve and clamped with a crimping tool on both sides. After that, this sleeve is wrapped with electrical tape or a cambric is fixed on it.

It is worth noting that the cores are placed in the sleeve either from different sides, or from one side. In the case of the first option, they will be connected in the central part of the tube. When choosing the second option, it must be taken into account that the diameter of the cores should not exceed the volume of the sleeve.

Of the advantages of such a connection, it should be noted:

• reliability;
• affordable cost of sleeves.

Disadvantages of the method:

1. The sleeve is used only once. This means that in case of repair it is torn off and a new one is fixed.
2. You will need to use a special tool for high-quality crimping on all sides.
3. Wires made of aluminum and copper are crimped only with special tubes that are difficult to find in stores.
4. Electrical wiring will take time.

Terminal connection

If the wiring is made of different materials, then it is recommended to use special clamps with springs or screws. It is not difficult to connect the conductors in this way, only a screwdriver is required in the work. The main thing is not to tighten the bolts with force.

Wiring safety

Upon completion of the installation of electrical wiring, it is necessary to carry out a set of measurements to make sure that the system is ready for the use of modern household equipment and technology. Checking the performance of the electrical panel, wires, cables, sockets, switches, makes it possible to correct the mistakes made in time. The test check shows that:

• wiring contacts have reliable grounding;
• connections are properly connected;
• there is no extraneous voltage and insulation damage;
• automatic protection apparatus matches the wiring.

It is possible to carry out an accurate measurement of electrical wiring only with the help of specialists in an electrical laboratory. For verification, control and measuring equipment is used, which shows losses, electricity consumption. Especially preventive inspection requires sockets, switches, lamps to avoid short circuits.