How to Change the Trimmer Wiring

The wiring of apartments of houses built in the 60s of the last century was calculated taking into account the load of up to 1 kW for cities whose population did not exceed a million inhabitants, and 1.5 kW for cities with more than a million people.

It is impossible to imagine a modern apartment without a microwave, water heater, refrigerator, air conditioning, the power of which often exceeds 1.5 kW, not to mention fireplaces, heated floors or modern electric stoves, whose power reaches 10 kW.

As you can see, the limits of the current load on the wiring, compared with the one that was half a century ago, increased several times. Moreover, the warranty period of operation of the electrical wiring does not exceed 20 years – then its insulation begins to collapse, which can cause a fire to the electrical wiring.

Previously, for electrical wiring in houses, it was mainly used aluminum wire with single insulation (APPV), because aluminum is much cheaper than copper. Aluminum wiring, compared with copper, is much worse able to withstand long current loads. Very often, modern standards, the use of aluminum wiring, due to the fragility and low reliability, is not allowed.

Improper operation of the wiring when its rated power is exceeded, leads to a significant reduction in its service life, and can also cause a short circuit.

Plan or wiring diagram

Before wiring replacement, it is necessary to draw up a large-scale drawing or diagram of the apartment on which to put the installation points of switches, sockets, illuminators.

How to Change the Trimmer Wiring

It is much more convenient when all consumers are divided into groups:

  • – lighting;
  • – sockets;
  • – electric stove;
  • – a bathroom.

A cable must be routed from the distribution panel to each group. Such a scheme, in the event of failure of one of the groups, ensures the work of the others. At the same time, you can save on the wire: the thicker it is, the more expensive. If you run one thick cable, then the branches will have to be done in junction boxes, and a large number of connections reduces the reliability of the wiring.

You should not connect all wiring to one group. It is recommended to connect the bathroom with a separate line, since it is a room with a high probability of electric shock. This fishing line is better equipped with a difavtomatom or RCD.

How to choose a machine?

In addition to RCD, it is recommended replacement of input machines in the switchboard. When choosing circuit breakers, it is necessary to use the rule: for lighting, a type B circuit breaker with a rating of 10 A is placed, 16 A on sockets.

The type of machine is determined based on the nature of the load. Powerful electric motors are not installed in the apartments, so general purpose machines are chosen.

How to choose wires?

Wires are the heart of electrical wiring. In most cases, the old wiring in our apartments is aluminum. In any case, you need to produce wiring replacement to a new one (preferably copper), because over time the insulation of the wiring crack, while the aluminum wires themselves quickly oxidize, they are very fragile on bends.

Instead of aluminum, it is necessary to install copper wires that have much lower resistivity (they conduct current much better). Also, copper wires are more flexible and convenient for installation (they are well soldered).

It is not recommended to connect new copper wires to old aluminum. These two metals have different chemical properties, therefore, in the places of such compounds, the oxidation process begins, which destroys the contact.

So, it is necessary to determine the wire of which brand the electrical wiring of the apartment will be laid. Very common for these purposes is a wire of the VVG brand, as well as a non-combustible wire of VVG NG.

Sockets must be powered with a three-core cable (phase, zero, protective earth) section not less 2.5mm2. Lighting can be powered VVG twin-core wire 1.5 mm2. The wiring for the electric stove is laid by a three-core cable, the cross section of which should be at least 4 mm2.

Wires are connected in several ways:

  • – twisting;
  • – using terminals;
  • – soldering.

The traditional way of connecting wires is twisting, but not everyone can make such a connection qualitatively.

Soldering is much more reliable, but this process is too long.

Using terminal blocks is a compromise between twisting and soldering.

How to remove old wiring?

First of all, it is necessary to turn off the batch switch in the switchboard to turn off the power to the apartment. Only then can the appliances and old wires be dismantled.

Dismantling the wires should start from the junction boxes. Usually their covers are on the walls under the ceiling. Opening them, you need to find the lead wire – it needs to be cut and insulated.

Next, all wires are removed. If the wire cannot be removed, it must be cut and insulated.

New wiring

After removing the old wiring, you can begin to lay a new one. In apartments, as a rule, hidden wiring is used, under which it is necessary to make strobes in the walls with the help of a puncher or a disk tool.

The gates must be parallel or perpendicular to the floor plane – the wiring must never be diagonal! This is done in order not to accidentally get into the wiring with a nail or drill, hanging a picture or, say, a shelf.

Junction boxes, switches and sockets are installed in recesses in the wall of appropriate sizes. They are easiest to do with the help of special drill bits.

You can also drill holes in a predetermined circle, and then refine the recess with a chisel. There is no need to give these holes a perfect shape – the plaster will fix everything.

Before making recesses for sockets and switches, you need to think about the height of their installation. Switches are usually installed at a height of about one meter, and sockets – 30 cm from the floor. However, no standards specify the height of their installation, the main thing here is the convenience of the inhabitants of the home.

Checking the quality of work performed

Video: How to Change the Trimmer Wiring


After electrical wiring and fixing in the channels of the wall, it is necessary to check the mounted fishing line for the absence of short circuits. A combination instrument, often called a tester, is usually used for this.

Only after checking the absence of a short circuit in the wiring of the line can it be connected to the voltage. After that, the performance of all lamps and sockets is checked using the same tester or phase indicator. Upon completion of calibration work, you can seal the channels with plaster mortar. Replacement wiring in the apartment is ready.

  • Stage 1 – Determine the front of work
  • Stage 2 – Determine the scheme and materials
  • Stage 3 – Dismantle the old fishing line
  • Stage 4 – Laying New Wiring
  • Stage 5 – Verification

Stage 1 – Determine the front of work

The first thing you need to start with is to find out in the management company or energy sales organization whether it is possible to increase the allocated power, since replacing the wiring without increasing the allocated power will not solve the problem of the knocking machine when the washing machine and electric kettle are turned on. Even if you were denied an increase in the allocated power, still calculate the wiring for the required load and lay a three-wire circuit in case of reconstruction of your house and replacement of the riser with the organization of grounding in the apartment.

Next, you must determine whether to completely change the line or only certain areas. Here, of course, it’s your business, but we can say with confidence that the buildings of the 60s used a small section of aluminum conductor, most likely without grounding, to create an electric network. This option is extremely dangerous and can not even be partially restored, so it’s better to replace the wiring in the apartment with your own hands once and be calm.

If the conductors are in this condition, the apartment wiring must be changed:

You must also evaluate your strengths and decide whether the wiring in the apartment will be replaced independently or if a specialist call is required. There is already a stick from two ends. On the one hand, there are no special difficulties in wiring the mowing line, but on the other hand, special tools, calculations and certain skills in working with electricity will be required. If you still want to test your strengths, then we will consider in detail all the stages of work in the form of step-by-step instructions.

Immediately recommend viewing the steps for replacing the wiring in the video:

Stage 2 – Determine the scheme and materials

Now we directly proceed to the settlement work. To get started, you need to draw up a wiring diagram yourself, which will indicate the installation locations of new switches, sockets, junction boxes and powerful household appliances that will be powered directly (for example, an electric stove).

We recommend that before starting the replacement, look at the wiring diagram in a one-room apartment, which provides the simplest option for displaying a lighting group and outlets in all rooms. Next, based on the scheme, you need to calculate the amount of materials, while choosing the most suitable characteristics.

It should immediately be noted that installation of hidden wiring is used in the apartment, which is associated with many nuances: electrical safety, the effect on the interior of rooms, fire safety, etc. At the same time, nobody forbids replacing the electrical wiring in the apartment with an open house with their own hands, it all depends on your preferences and strengths.

We advise you to adhere to the following recommendations in order to replace the wiring correctly:

  1. The cable is copper, three-core, with a cross section of at least 2.5 mm 2 for the outlet group, 1.5 mm 2 for the luminaires and 4 mm 2 for powerful electrical appliances. We recommend that you calculate the cable cross-section in order to accurately determine the appropriate diameter of the cores. As for the brand, it is better to give preference to an expensive foreign NYM marking product. From domestic, which are cheaper, we recommend using VVG or better VVGNG-LS.
  2. Protective Automation. You can’t do without it, because when replacing the wiring in the apartment, it is necessary to protect the wiring from current leaks, short circuits and overloads. For this, an UZO and a circuit breaker (or a combined device – difavtomat) are used. The machine and RCD have various characteristics that are selected based on the loads on the fishing line. For example, for a three-room apartment, it is customary to install 16A machines on sockets, 10A for lighting, 32A for a powerful electric stove. The rating of the opening circuit breaker on the switchboard is indicated in the power supply contract, as limited by allocated power. The residual current device is set to a value higher than the machine. From manufacturers, we recommend giving preference to leading companies – ABB, Schneider Electric and Legrand.
  3. Junction boxes for the apartment are selected based on the branching of the groups and the cross-section of all conductors. Rectangular and square boxes are more capacious, but round ones are much easier to install.
  4. Sockets must be grounded, to protect against children, purchase products with special curtains that will prevent foreign objects from getting inside. Pay attention to product labeling so that the outlet can withstand current loads, otherwise problems can not be avoided in the future when connecting powerful household appliances.
  5. Twisting is forbidden to use, the list of allowed connections is given in PUE 2.1.21 (Chapter 2.1 of the PUE), but we have listed them in the next paragraph.
  6. Conductors of wires and cables can be connected using screw and spring clamps and terminal blocks, welding, soldering, bolts, using pressure testing. Currently, one of the most convenient and popular types of connection are the wagon terminal blocks, they are great for most cases and easy to use. Crimping with sleeves is a good type of connection, but a special tool is required. Nevertheless, the most reliable connection is welding and soldering, but also the most time-consuming. You can read more about this issue in the article https://samelectrik.Ru/sposoby-soedineniya-provodov-v-raspredelitelnoj-korobke.Html
  7. There are no special requirements for switches, the main thing is that they are convenient and safe. Among all types of light switches, keyboards and dimmers are popular.

Stage 3 – Dismantle the old fishing line

Now you can replace the old wiring. To do this, be sure to turn off the electricity at the entrance to the apartment, remove all the interfering furniture and begin to destroy the wall decoration.

The wiring in the apartment is replaced by junction boxes in each room. These electrical “dots” can be detected by plastic covers in the wall or eye-catching contours through the wallpaper. The lid is twisted, after which all twists are disconnected, and the old cable is carefully released from the putty strobes. You can also find a wire in the wall using a homemade metal detector, which is created from improvised tools in a matter of minutes.

We draw your attention to the fact that in some places the fishing line cannot be removed from the wall without significant structural damage. In this case, you can do without gating if you cut off the problem area and carefully insulate it, leaving it in the old gate!

Stage 4 – Laying New Wiring

Now the most important thing is that you need to independently replace the wiring in the apartment with a new, more reliable one.

We will not dwell on this stage in detail since We examined the installation of electrical wiring in the apartment in detail in the corresponding article.

When the replacement of the apartment wiring is completed, it is imperative to photograph the wiring of the cable along the walls. This is done so that if problems arise, you can easily find the damaged area in the photo.

Do not rush to cover the gates with a solution, you need to do this after all the wiring has been checked for operability.

The video below demonstrates an example of a new wiring in an apartment, after replacement:

Stage 5 – Verification

Well, the last, no less important event – the dialer of the new wiring in the apartment with a multimeter. This device will allow you to determine the performance of the wiring and the presence of a short circuit, if you suddenly connected something wrong. If the device does not show errors, then you can connect the finished fishing line to the input shield and check the operability of all lamps, switches and sockets. We talked about how the cable is run in a separate article.

If all elements of the circuit work, turn off the power again and proceed to shutting down the strob. On this, the replacement of the wiring in the apartment with your own hands is considered complete. As you can see, the event is quite time-consuming and requires skills, but still, with great desire and care, you can independently carry out electrical installation. We hope our step-by-step instructions were useful and understandable for you!

Finally, we recommend watching a video, thanks to which it will become clear whether it is worth changing the old wiring in the apartment or whether you can do with a partial replacement of the mains: