Correct connection of wires in a junction box - Ways and Advice

Any wiring diagram contains some connections, branching wires or cables. Even a person who is far from electrical engineering knows that in his apartment, in every room, under wallpaper or plaster, there are special boxes in which electrical wires are connected. They are also called "nozzle".They are round, made of polymer material and covered with a lid. Place them under the ceiling( 20 cm below).So we'll figure out why they are needed, and how to properly connect the wires in the junction box.

Why the junction box is needed

Quite often there is some disdain for the switch box. Some people believe that using it when laying wires is a waste of time. After all, it needs to be fixed on the surface, and this is additional effort. It is much easier, for example, to twist the wires, insulate the connection point and "roll up" all the plaster. But at the same time some questions are overlooked:

1. During operation, free access should be provided to the wire connection points. For example, if there is no light in a room or an outlet is not working? The check showed that the reason is in the absence of tension. How to find the faulty part of the chain? Tear off the wallpaper, smash the plaster to get access to the twisting of the wires?
2. If in the future you will need, for example, to put in addition one more( two, three) sockets. Connect them "in parallel" from the first? Is it always convenient? While it is not possible to connect new wires in the switch box;
3. Correct connection of wires - using terminal connectors. What depth do you need to hollow the "channel" in the wall to hide the terminal strip there?
4. In terms of fire safety, the advantage of such a box is undeniable.

Wiring options for

1. wires Using terminal blocks. This method is most preferable in all respects. Such terminal blocks are sold everywhere, and they cost "pennies".Having small dimensions, it is easy to fit into the switch box. There are up to twenty pairs of contacts on the terminal block. The shoe itself is made of soft "plastic", so you just need to cut off the required number of pairs and connect the wires, putting the assembly in a box. You just need to think about the perspective and leave a couple more - three free contacts. It will come in handy someday;
2. Soldering of wires. This is quite problematic, and it is unlikely that a person who does not have experience in such matters will be able to perform such a job qualitatively. Especially when it comes to aluminum wires. And time it will require quite a lot, and it is inconvenient to work under the ceiling. Therefore, this method is more for a professional. Personally, I have always used terminal connections - it's quite reliable and convenient;
3. Wire twisting. A simpler method than soldering, but less suitable. First, if the twist is unreliable, then the wires can spark. Everyone knows what can happen from a single spark;
4. Crimping. Quite a troublesome occupation, which requires the purchase of a shrink tube, special sleeves, and experience, too.

All methods, except the use of terminals, require insulation of the wire connections. For this, special sleeves are used, which are put on the twist. Although some "experts" are isolated with a usual tape. Again - this is an "amateur", the difference between special sleeves and a good insulation tape in domestic conditions will be small.