During the repair process, the owners of the house or apartment are faced with the need to complete the installation of junction boxes. The wires in them must be installed correctly. The best known method in this case is twisting. It has certain advantages and disadvantages. Almost everyone can do the twisting in the junction box with their own hands. But you need to learn about all the nuances of such work. How to perform the twisting will be discussed later.
Where to begin?
One of the oldest ways to connect electricians is to twist the wires in the junction box. How to perform a similar procedure? Before embarking on a similar task, you need to consider all the features of this process.
You need to understand that an improperly executed connection poses a potential threat to the residents of the house, their neighbors. Twisting used to be the only way to connect wires. But over time, this technology has improved. People began to use more electrical appliances that have high power. Therefore, the electrical system today is subject to significant loads. Regular twisting, unfortunately, does not withstand such an impact.
It must be remembered that the connection of the wires in the junction box according to the PUE cannot be performed using ordinary twisting. During the construction or reconstruction process, it is impossible to commission an object that has wires connected in this design in this design.
However, twisting does not lose its relevance today. Its advanced varieties are applied. Normal is used by home masters when connecting wires with a slight load. The connection is the weak point of the entire electrical system, so it must be done correctly. The consequences of neglect of the requirements of the PUE will be not only a possible electric shock to users of the power grid, but also the possibility of a fire. In this case, the unlawful actions of the owners of the house or apartment may become a reason for bringing them to criminal liability. To prevent this from happening, you need to do all the work on connecting the electrics correctly.
Common mistakes
Before starting work, you need to familiarize yourself with the established requirements for twisting the wires in the junction box according to the PUE. This will avoid errors. A novice electrician must study all the requirements that are put forward by similar rules for creating connections.
Some masters neglect personal security requirements. They use an improper tool that does not have protection against electric shock. It is also important to work in rubberized shoes by turning off the power in the apartment or house. These are simple rules that must be followed in the process.
Twisting the electrical wires in the junction box must be done according to the established procedure. It is not permissible to wind one wire over another. This mistake is often made by novice electricians. Veins without fail should be evenly wound on one another. Only in this case the entanglement can guarantee sufficient mechanical strength of such a connection. The current in this case will pass through the conductor correctly. Such a connection with proper operation will last for many years.
Many wizards make a mistake when choosing the length of the twist. Its size must comply with the requirements of the instructions. Too short a connection breaks easily. There is a definite relationship between the length of the twist and the thickness of the wire. The thinner it is, the shorter the connection can be. Thick veins require a long twist.
Varieties
How to twist wires in a junction box? There are several ways to do this. Having performed them correctly, you can create a high-quality connection that will be safely operated for several decades.
It is worth adhering to a simple rule, which states that with the help of twisting, only the same type of wire can be connected. If they are different, you will need to use special terminals, clamps. Electricians most often use the following types of twisting:
- simple;
- groove twisting;
- bandage.
These methods can be applied in parallel, sequentially or with a branch. Each subspecies has its own characteristics. So, a simple way of connecting wires using twisting is widely used by home craftsmen to make connections in a junction box. However, to increase its reliability, additional elements are used, for example, special caps.
If it is necessary to connect the conductors of large diameter, bandage twisting is used. The groove technique is mainly used for aluminum wire. It is very important to make such a connection with a high degree of accuracy.
It is worth noting that the twisting of the wires in the junction box using the presented methods is applied only if the cross-section of the conductors does not exceed 10 mm². Usually, wires with a cross section of 1.5 or 2.5 mm² are used in domestic conditions.
In which cases twisting is unacceptable
In some cases it is unacceptable to use twisted wires in the junction box. How to make the connection correctly is indicated in the EMP. Of course, regardless of the requirements of the standards, twisting remains the most popular type of connection. Both professional and novice masters will not refuse it.
But it should be remembered that over time, this fixation gradually weakens. This is due to residual elastic deformation of the cores. At the attachment point, the transition resistance increases, which leads to overheating of the wire. In this case, the connection is broken. Only competently performed twisting will last a long time.
In some situations, due to the nature of such a connection, you cannot even think about its use when connecting. Such a limitation can be a current in an electric circuit that exceeds 3 A. It is also categorically excluded to use the type of connection presented if the box is in combustible material.
If the master is a professional electrician, he is also forbidden to use this method of switching. Otherwise, he will be liable, up to criminal punishment. The master, who connected the wires using the presented methodology, exposes customers to potential risk. If a fire occurs (which is not uncommon when using twisting), the fault lies entirely with the electrician. Therefore, masters today avoid using this method in the performance of their professional duties.
Simple twist
If, for example, you need to twist the copper wires in the junction box, which are of the same type, you can use the following instruction. It is necessary to disconnect the voltage in the network. Further, both veins must be cleaned qualitatively. But at the same time, you must act carefully so as not to damage the core.
The length of the twisted wires in the junction box can be different. But the standard is considered to be 5 cm. This is enough to create a strong connection on the wires 2.5 mm².
You can use a special tool for twisting the wires in the junction box. With it, it is easy to remove the insulation from the wire without damaging it. After that, the exposed contacts must be wiped with a cloth soaked in acetone. Degreasing the surface, you need to clean the ends with sandpaper. Processing is carried out until a metallic color appears.
First, the veins are crossed, and then they are twisted using pliers. You need to act carefully so that the turns are uniform. It should turn out at least 5 turns. The finished twist is isolated. For this, electrical tape is used. Instead, it is better to use heat shrink tubing. They are also called Cambrians. Such materials will qualitatively protect the junction from the adverse effects of the environment. If you perform all the steps in accordance with the instructions, you can get a reliable fixation of the wires. This method is best used for copper wire.
Twist single and stranded wire
A more difficult task is to fix the single-core and stranded wires. In this case, it is also recommended to resort to a different technique. But if there is no other way out, then it is possible to twist in the junction box 6 wires of a multi-core type with a single-core cable. You need to act according to the instructions, not neglecting any stage of the work.
First, the wires are exposed using a special tool. If not, you can use a knife, but you need to proceed with caution. The length of the exposed core should be at least 5 cm. Next, the ends of a single or stranded wire are treated with acetone and sandpaper.
When the preparatory work is completed, the two wires are crossed and at the distance of 2.5 cm from the edge they begin to wind the stranded wire.
Considering the method of how to twist the wires in the junction box, you should pay attention to the wrapping process. All thin veins should lie flat on the mono-core. Further, with the help of pliers, the free end must be bent towards the turns. A single-core wire will tightly press the area onto which the multi-core is wound. The compound is isolated using cambric.
The same technique is used if it is necessary to fix two stranded wires. It is worth remembering that it is impossible to connect aluminum and copper wires. This action will lead to the rapid destruction of the junction. As a result, a short circuit will occur, the wire will overheat. This may cause a fire. Therefore, you need to combine only identical materials.
Professional Tips
Experts give advice on how to twist the wires in the junction box. If the owners of the house nevertheless decided to choose this particular technique for connecting the cable cores, it is best to solder or weld the mount point in addition. This will greatly increase the security of the connection. It will become inextricable, and therefore reliable. If the cores have a large cross-sectional diameter, the application of the additional steps presented is mandatory.
Experts advise using Wago terminals when connecting wires . This will greatly simplify the mounting process, as well as make the operation of the electrical system safe. With the help of such devices for twisting wires in a junction box, it is possible to switch cables from copper and aluminum, wires of different sections.
Another reliable method of fixation is the use of PPE clamps. These are inexpensive devices that increase the security of the connection several times. Do not save on your own safety. Modern fixtures are affordable. They provide a high level of security.
If the fixation was performed by twisting, do not immediately hide the wires in the box. You need to turn on the network, and then the electrical appliances. For several hours at maximum load on the line you need to observe the place of twisting. Only if everything is in order with him, you can install them in the place intended for this. If the mount heats up, you need to redo the work again. This means that the junction turned out to be unreliable.
Soldering or welding
The twisting of wires in the junction box will be reliable if it is soldered or welded. To do this, you need to use special tools and materials. Having cleaned the ends, they are twisted. Actions are like a simple twist. But after creating such a connection, the twisted ends are dipped into the previously melted solder. The cores are then lowered into the soldering bath. When the material cools down, you need to additionally protect the attachment point with cambric. You can also use electrical tape.
It is also permissible to use a soldering iron. But this method is almost impossible to apply if you need to solder 3-4 cores with a standard cross-section (2.5 mm²). In this case, welding can only be done if the tool has a thick copper tip. It should be characterized by high heat capacity. The power of the soldering iron should be at least 40 watts (better than 60 watts).
It is worth noting that it is strictly forbidden to cool down the place of fixation when using the soldering method in cold water. The mount in this case will turn out to be of poor quality. They appear in the material due to a sharp drop in the temperature of microcracks.
Advantages and disadvantages
The twisting of wires in the junction box, reinforced by soldering, has high reliability and quality of the fixation point. But this technique has certain disadvantages. You need to know about them before starting work.
The disadvantage of soldering is the need to purchase a special tool that you need to be able to handle correctly. The fixing process in this case is very laborious. The end result is ultimately inseparable. To disconnect the wires, they will need to be cut. The conductors will be shortened.
PUEs also limit the application of this approach to residential premises. In combustible materials, the use of this type of compounds is unacceptable. Over time, the place of soldering loses voltage, the conductivity index decreases.
Using a screwdriver
Using a screwdriver, you can create a uniform twist. In this case, the use of additional devices is not required. Wires are prepared for the connection. The ends of the cable bend and install them in the chuck of a screwdriver. It needs to be clamped. Next you need to click on the tool button. Turnovers should be set small. The wire must be held with pliers. When the twist is done, the ends are cut off. Further, you can isolate the twist using cambric or electrical tape. But it is better to further strengthen the connection by soldering. A screwdriver ensures uniformity of wire wrapping on each other. This improves the quality of the connection.