Wiring in the junction box

Junction boxes perform a very important function. They provide the distribution of electric wires between the points of consumption, i.e.switches, lighting devices and sockets.

Have you decided to install the above devices yourself? Then you need to thoroughly understand the features and order of connecting cables, as well as the basic methods of their connection.

For a better understanding of the process, this event will be considered in several stages: from the preparation of the necessary materials to the connection of electrical appliances using the example of an outlet, a two-button switch and light bulbs. Beforehand, you will learn about the basic ways of connecting the cables and the features of the box switching.

Wiring methods

There are several methods of connection of cables. You can choose the most convenient and suitable for your case option.

Twist

Currently, the connection of cables in junction boxes by the method of twisting is prohibited - it is considered extremely unreliable in comparison with other existing options. When choosing a twist, you consciously take all possible responsibility for yourself.

The connection itself is extremely simple: about 10 mm of insulation is scraped off the wires, and afterwards they are carefully wound on each other. When connecting wires with a diameter of up to 1 mm, we perform at least 5 turns, in the case of twisting more "serious" cables - from 3 turns.

Crimping

A popular connection option. Performed using a special sleeve to the size of the bundle of wires. The material of the sleeve must also correspond to the material of the cable making.

Crimping tools are used for pressing the pliers for crimping sleeves. Folk craftsmen often try to crimple using pliers, but professionals recommend that you refrain from this option, becausethe connection will not be so reliable.

The operation is performed in the following order.

The first step of the

We remove the insulation from the wires, focusing on the length of the used sleeve.

Second step

We twist the wires into a bundle and insert them into the connector.

Third step

Crimping the sleeve with wires press mites.

Fourth step

We carry out isolation of the finished joint by heat shrinkage or conventional insulating tape.

crimping process

welding After performing such a connection, essentially a solid wire is obtained, which is not afraid of oxidation processes, nor other negative effects characteristic of detachable methods.

To connect the wires using the welding method, the following should be prepared:

• welding machine at 24V with a power of 1 kW;
• flux;
• carbon electrode;
• protective equipment( gloves, mask / goggles).
  

  Welding diagram

We work in this order.

First step

Remove the insulation from the cables and clean the wires to a shine. To do this, we use sandpaper.

The second step

We connect the wires using the twisting method.

Third step

Pour the flux into the recess of our electrode.

Fourth step

We turn on the welding machine, press the electrode to the cables and hold it until the ball is formed - the so-called"Contact point".

Fifth step

Clean the obtained contact point from the flux and coat it with varnish.

In the end, we can only isolate the finished connection.

Soldering

The procedure remains the same as for welding wires. The only difference is that the cables are connected with solder, melted with a soldering iron. Molten solder should flow into the inside of the twist.

Important note! The connection is very reliable and durable, but from the use of it in places where the cables can become very hot, professionals recommend refraining.

It is also not recommended to use soldering in the places of possible mechanical loads on the connection.

Screw connection terminals

An excellent method of fast and simple connection of wires in a junction box. Compact, inexpensive clamps allow the connection of both homogeneous and dissimilar conductors.

Work is done in two simple steps. It is necessary to do the following:

• clean off the ends of the wires with about 5 mm insulation;
• insert the wires into the clamp and tighten with a screw.

Important! Monitor the clamping force so as not to disturb the integrity of the conductors. In particular, use caution when connecting aluminum wires.

Bolted connections

The connection is reliable, but very cumbersome. Suitable for the same bulky boxes of the old model. In a modern box, a bolted connection can simply not fit.

The operation is performed in the following order.

First step

We put a steel washer on the bolt.

The second step

Top with the bolt one of the connecting wires. Beforehand, it is necessary to clean the insulation and form a ring from the cable. With the second wire in advance we do the same.

Third step

Put on the next steel washer.

Fourth step

We put on the second wire ring.

Fifth step

We put on the last washer and tighten the connection with a nut.

Of course, the bolted connection also needs insulation, which will not be reflected in its dimensions in the best way.

Self-clamping connections

The most modern and popular option to date. The clamps are extremely simple to use. In addition, within such compounds, there is initially a paste excluding the risk of oxidation of metals, which makes it possible to insert heterogeneous conductors without any fear.

We work in this order.

The first step. Take approximately 10 mm of insulation from each wire.

The second step. Lift up the clip lever.

The third step is .We insert the conductors in the connector.

Fourth step. Lower the lever.

Clips without levers simply snap into place.

We study the circuit for the

box. When connecting the wires in the junction box, it is very important to know the features of the marking of each cable. This will create a safe, reliable and generally correct connection.

For example, the wires "zero"( in the diagram they are blue) and ground cables( denoted in yellow) are connected in the corresponding way in colors, as shown in the picture. With the arrangement of two-wire wiring, the circuit remains the same, except for ground wires.

More difficult is the phase-breaking procedure( indicated by black or red).If only the cables for connecting the socket are passed through the box, the phase wires are also connected together.

luminaires If the cables from the box go to a switch with one button, the wire that goes to the switch must be twisted with all the phase wires. The same cable that departs from the switch is connected to the phase wire that goes to the lighting fixture. As a result, 4 connections will be made.

In the case of connection via a junction box of a switch with two keys in the conditions of a three-wire electrical wiring, a cable with four cores is run on the chandelier. If the wiring is two-wire, the number of veins is reduced to three, becauseGrounding is excluded from the circuit, as shown in the figure.

box isolation Without taking into account the separate twisting of the earthing switch, 4 connections are created in the box. All the wires "zeros"( marked in blue) are connected to each other.

The phasing of the sockets and the supply cable are twisted together, and then they are connected to the common terminal of the switch with two keys. From the latter, 2 separate wires go to the lighting fixture.

Thus, in the desoldering of the box there is nothing super complicated. It is only necessary to understand the features of the designation of wires and the order of their connection. After that, you can begin to consolidate the theoretical knowledge gained in practice.

Installation and connection of the junction box

You are invited to familiarize yourself with the features of all the key stages of connecting the junction box: from the wiring up to the connection of electrical appliances.

The first stage - getting ready for work

First of all, we prepare everything that is required to connect electrical appliances to the box. The kit includes:

• cables 3x2.5, VVG;
• cables 2x2,5, АВВГ;
• switch for 2 keys;
• mounting;
• lighting;
• outlet;
• round pliers;
• measuring tape;
• cutting pliers;
• pliers;
• flat-blade screwdriver;
• hammer.

The second stage - marking

working surface marking. At this stage we place the places of installation of electrical appliances and the way of passing the wires. So we can calculate the right amount of materials for the installation of the system.

The third stage - we proceed to installation

We first turn off the supply of electricity.

We supply wires to the junction box. As a rule, the cables are laid in stitches. To secure the cables, small nails or special plastic clips are used. In the case of doing work in a wooden house, the wires will be fed through special installation boxes.

Important note! Wiring should be routed so that the cables do not overlap. In the case if crossings are inevitable, such places need to be isolated especially carefully.

The fourth stage - we connect electrical appliances and connect the wires

terminal blocks We set up about 10 cm of wire in the preassembled wall or fixed on the base( depending on the model).We remove the cables from the cables. Then remove approximately 0.5 cm of insulation from each core. In this moment we are guided by the situation - we clean so much insulation that the veins could be connected by the chosen method.

The diagram shows an example of connecting electrical wires via terminal blocks.

In the example under consideration, the connection is made using a two-wire wire in which one core is zero, the second is a phase. On a zero we connect a socket and lighting devices. The phase supply wire is connected to the outlet and one residential cable of the switch.

In our example, the switch is two-key. Each key is responsible for monitoring a separate group of lighting devices. The second wire of the switch cable is connected to the first button, the third wire is connected to the second key.

In the junction box, zero wires are connected from the socket and bulb holders. The power supply cable is connected: zero is marked in blue, the phase is red. The wires are connected to connect each switch button to the lamp holders.

The fifth stage - check the operation of the

system We turn on the power supply and check the operation of our outlet and switch. Everything works fine. We did an excellent job.

Now you know the order of connecting the wires in the junction box and the connection features of each main electrical appliance. Using the information obtained, you can independently cope with all planned activities.

Have fun!

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