Have you ever experienced a sudden power outage of home appliances or lighting? Then a long and unsuccessful attempt to change the lamps in the chandelier. Or trying to plug another electrical appliance, such as a kettle, into the TV socket to determine the presence of voltage in the network.
Why contact is lost
The most common cause of network problems is weak contacts of connected wires in the distribution box. As a result, the circuit is broken when a large load current flows, and the insulation of the wires ignites. Overheating usually occurs when new powerful devices are connected to the home network.
Electrical installation rules prohibit simple twisting of wires, which is popular among DIYers. The PUE standards require ensuring mechanical strength and electrical resistance at the point of contact of the connected wires no less than those specified in the parameters of the wires themselves. Because over time, the wires at the twisting point oxidize from the linear expansion of the metal under the influence of current. Accordingly, the contact disappears, the probability of a short circuit increases.
4 Correct Methods of Connecting Wires
Before you start renovating your apartment, you should familiarize yourself with reliable electrical installation options. Even if you don’t do these jobs yourself, useful knowledge will come in handy for monitoring the process.
Welding of wires
The most durable method in the process of repairing home wiring is rarely used. Because welding requires skills and special equipment.
The connection is made in the following way: the twisted wires, stripped of insulation, are clamped, fixed and welded. Then the cooled contact is insulated with caps or a triple layer of electrical tape.
Soldering wires
The method requires soldering skills, solder, rosin and insulating caps. The technology is similar to welding. The non-separable connection may have to be removed in subsequent repairs.
A distribution box with soldered wires inside is called a junction box. Soldering is prohibited by the Electrical Installation Code for lines with high load currents. Because over time, the contact resistance at the soldering point increases anyway.
Crimping of wires
Crimping of stripped wires provides sufficiently high quality. The connection is made using a sleeve placed on twisted conductors. It is important to use sleeves made of the same metal as the cable wires.
One-time fastening requires a special tool – a pipe cutter, crimping pliers. You will not achieve the required contact resistance with ordinary pliers. Labor-intensive crimping is in demand for connecting wires with a high load, as well as welding.
Mechanical wire clamp
The simplest quick connection of similar and different wires is made with the help of self-clamping elements. The bare end of the wire is inserted into the clip and clamped with a lever. When connecting conductors of different cross-sections, ordinary terminal boxes are used. In the case of different conductive metals, you will need non-standard blocks with a special composition that protects the contacts from oxidation.
You can install a box that already has a terminal block with reliable self-clamping terminals or screw contacts. You don’t need to buy any elements for them, you only need a screwdriver. This convenient method is used for consumers with a small load. With the help of such a distribution box, lines are connected for lighting, for sockets to household fans, as well as for computers and telephone chargers.
The Importance of Being Able to Calculate Risks
Such minor troubles as a sudden power outage are nerve-wracking and time-consuming. But believe me, melted food in the refrigerator on a summer night is not the biggest problem. But a burnt-down apartment, a lawsuit by tenants for several hundred thousand rubles against the owner of the burnt-down apartment – these are more serious situations. Not to mention dead pets or injured people.
Agree that not always a master found through an ad or even a certified electrician will do everything correctly and efficiently during the repair process. Therefore, armed with knowledge, you will be able to evaluate their work. Or make all the connections yourself, if you have the necessary skills. And then for many years you are guaranteed not to have problems with strong wire contacts in distribution boxes.