The wiring in apartments in old-built houses in most cases has already exhausted its resource and needs to be replaced. In addition, old household networks are absolutely not designed for the power of modern household appliances. Of course, when buying new cables, some important factors should be considered. About which wire to use for wiring in the apartment is best, and we will talk in this article.
What to consider when choosing
The first thing to decide is the cross-section of the future cable. This parameter depends on such factors:
- network length, and therefore resistance;
- estimated load on it;
- manufacturing material.
When deciding which wire to use for wiring a short network with a large load in an apartment, you should focus on the heating conditions. The cable cross section for long lines to a large extent depends on the magnitude of the resistance. Also in this case, mechanical strength is important.
As for the material of manufacture, at the moment two types of cables are used: copper and aluminum. In the first case, the cross section will be smaller, in the second - more. For this reason, the vast majority of apartment owners currently prefer to run copper cables in apartments that are characterized by better conductivity.
Power consumption
The cross-section of the electrical wiring in the apartment should be such that the owners subsequently had the opportunity to connect devices of the required power. The current value for this particular household appliance is determined by the formula I = P / V, where P is its power (you can see it in the data sheet), V is the voltage in the network. In households, it is usually 220 V. Thus, for example, for a heater having a power of 2000 W, the current value will be 9 A.
Next, the total current of all prospective consumers is calculated. The cross-section of the copper wire is selected taking into account the permissible 10 A per square millimeter. Aluminum - 8 A. In the event that the wiring is hidden, these values should be multiplied by a correction factor - 0.8. Open wiring in the apartment is practically not used. However, if for some reason you have to choose this option, you should use a wire with a cross section of at least 4 mm 2 having sufficient mechanical strength. With greater accuracy, the permissible current load on copper and aluminum cables can be found in the special tables.
It is better to choose wires for wiring in the apartment with a certain margin of power. This will make it possible to subsequently connect new electrical appliances to the network, the purchase of which is not currently planned.
In ordinary city apartments, the most common choice for lighting is a copper wire with a cross section of 1.5 mm 2 , for outlets - 2.5 mm 2 . It is better to stretch a 4 mm 2 cable into the kitchen, since there are usually a lot of powerful household appliances - a stove, a refrigerator, a dishwasher, etc. The installation cable for the entrance to the apartment is chosen so that its cross section is one step higher than necessary for the most powerful the device to be used.
Resistance
The question of which wire to use for wiring in the apartment comes down to including the correct selection of the cross-section in terms of possible voltage losses. The lines even in urban apartments are quite long. In this case, the voltage loss in the cables can reach an unacceptable value. The choice must be made in such a way that this value does not exceed 5%. To calculate the voltage loss, you first need to calculate the load moment. For this, the power in kilowatts is multiplied by the cable length in meters. Further, according to special tables, the actual percentage of loss is determined. It will depend on the moment of load, the cross-section of the cable and its length. There are separate tables for three-phase and single-phase networks. However, you should be aware that they indicate the percentage of losses without taking into account the heating of the cable when current flows through it. Therefore, in this case, you should also choose a wire cross section with a margin. That is, look at the table for the value corresponding not to 5, but 4%.
Soft wires
For residential premises, soft flexible cables are usually chosen. Each core in this case consists of a large number of thin conductors. Such cables are easy to pull through complex apartments with many bends. The only drawback of soft wires is that when you connect the wires, you have to crimp them and press on a special tip on them.
Hard
There is another kind of cable - hard. In this case, each core consists of one conductor. In principle, it does not matter which wires for wiring in the apartment will be selected - flexible or rigid. The main thing is that the cable meets the load on it from consumers. For a city apartment, three-core options with a ground wire are usually chosen. The core insulation in this case will have different colors. Brown or red correspond to the phase wire, blue to zero, yellow to ground.
Most commonly used wire brands
One of the most popular options is the NYM cable, which is very good for wiring in an apartment. It is a flexible version of single-wire conductors and has a round shape. Another of its advantages is the presence of two insulation. The latter circumstance makes it more fireproof.
Another variety often used in urban apartments is a single- wire VVG cable, which can be round or flat. This option is more compact than NYM, and, accordingly, more convenient to lay. Among its advantages, among other things, can be attributed not too high cost.
The third common option is multiwire PVA. This round cable has very good flexibility. Most often it is used for household appliances as a network wire. However, for the installation of lines, it fits very well.
What else you need to know
In the event that the wiring is supposed to be pulled behind a drywall finish or a false ceiling, a cable that does not support combustion should be used. Such options are marked with the letters "NG". Better yet, use a non-flammable cable with an “ls” index. Insulation of such wires in case of fire will not emit a lot of harmful smoke and gases.
It is best if the cable for wiring in the apartment will have double insulation. In any case, saving on this is not worth it. Otherwise, for example, during flooding in an apartment, a fire may also occur, since a single insulation is often quite simply damaged during installation or during operation.
How to choose switches
So, you have decided which wire to use for wiring in the apartment. However, cables are, of course, far from the only network element. In addition to them, you will need to buy other components as well. The switches are selected, first of all, based on whether the wiring used in the apartment is open or closed. Of course, the first option in this case is used extremely rarely. Therefore, for a city apartment, most likely, you will need to purchase switches for hidden wiring.
In addition, these network elements come with screw and screwless clamp. The first option can be a good choice if the electrical wiring in the apartment is stretched using aluminum cables. The latter, over time, can slightly melt and begin to sparkle. In this case, it will be enough just to tighten the screws. For copper wiring, switches with terminal clamps are usually chosen. They are more convenient when connecting.
Outlet selection
This element is best chosen based on the manufacturer. However, one must beware of fakes. In the latter case, for example, an unpleasant odor can come from sockets. In addition, low-quality goods are often made of too thin or soft plastic. The socket must be heavy enough. It is also worth paying attention to the state of the grounding contact. He must not bend.
It is worth taking a plug with you to the store and trying to plug it into a power outlet. Of course, she should not hang out and fall out. For such an option as external wiring in the apartment, as in the case of switches, sockets of a special design are used.
Today on sale you can also find special types of sockets, equipped, for example, with USB connectors or LED-backlit. If desired, you can choose this option.
Well, hopefully, our article will help you decide which wire to use for wiring in a city apartment. There are many options at the moment. The most important thing is to use cables that are suitable for the power of the devices and as safe as possible.