What are the functions of junction boxes? This question is fairly easy to answer. When installing a switch, lamp or socket, each self-respecting electrician takes all measures to ensure that the junction box is as close to the work object as possible. This is understandable, since you can save the cable, and you won’t have to do the extra work on laying the route, which is why there can be up to three such devices in each room.
However, their main purpose is not to save materials and working time, but that with their help the cable cores are protected from external sources, including moisture and dust, mechanical damage is also eliminated.
In both the first and second cases, the consequences will be unpleasant, so the installation of junction boxes is simply necessary. In each household, these devices are required. In addition, the junction box is also needed as an object of aesthetic perception, since it covers the unsightly ends of the cable, as well as the terminals or caps used in the wiring.
There are several types of junction boxes. It should immediately be noted that these devices have been used for a long time in the construction and installation, and during this time they have undergone many changes. The following boxes appeared for use:
- which are installed on hollow walls;
- cable junction box;
- square;
- boxes for concealed and open wiring.
Let's consider some of them. Without a doubt, the “queen” is a junction box, which is used for external wiring, which is an ordinary round glass made of thin metal, covered with a lid on top. Since they are airtight and not amenable to burning, the function assigned to them is fulfilled one hundred percent. They can still be seen today in houses of old construction. Quite often, when there were no such boxes available, cans were used instead. Undoubtedly, such boxes are durable, they are used in modern construction, however, most often in industrial construction. But in spite of everything, this device remains metal, and this is a rather expensive material, it is impractical to spend it on such a trifle as a box. To be honest, such a device is not always convenient, since in case of need it will be difficult to make an additional hole for input, and also if necessary, increase its diameter.
Therefore, with the development of such a material as plastic, a junction box made of it appeared, it is currently becoming especially popular. They are made of durable material that does not support combustion. Such a device is used when installing hidden and open electrical wiring.
It should be noted that it is strictly forbidden to close junction boxes of any kind with tiles, as well as to block with all kinds of designs. This cannot be done based on their considerations of accessibility to them.