It is often difficult for inexperienced craftsmen to find hidden wiring in the walls. However, you can cope with the task, knowing some of the principles of work of improvised and special devices.
When to find hidden wiring
The search for a cable laid in the wall is performed in the following situations:
- Overhaul with redevelopment of the premises. In order not to damage the wires, you need to know where they are located.
- Displacement of existing power points to other places for a more convenient location of equipment and lamps.
- Broken wiring in one of the areas of the room. Here you need to find the problem area and fix the problem.
In case of a complete replacement of the old wiring with a new one, you also need to find a cable so as not to intersect with it when laying new strobes or, if necessary, lay other wires into the existing channels.
Benefits of flush-mounted cable
The hidden method of installing electrical wiring in an apartment or house differs from the external one in that all cables are not visible to the eyes of households and guests. The advantages of this installation method are as follows:
- After finishing the strobes with putty, the wall is ready for finishing. The master can arrange the design of the room at his discretion.
- Conducted wires are less hazardous to the user than open cables. Hidden communication cannot be damaged by accident.
- When laying the cable in a secret method, use the path from the junction box, which is laid strictly vertically and horizontally. This is a cost saving for the purchase of the required conductive products.
Retro wiring and open cable laying according to SNiP are used in wooden cottages. It is difficult to hide it, as it contradicts the fire safety rules.
Special devices for finding a cable
According to the PUE, the wiring in the wall is laid only straight. Turns are performed at an angle of 90 degrees. Diagonal grooves and channels are strictly prohibited. Therefore, when searching for a cable in the wall, the master, using any kind of device, should only move horizontally or vertically. This is logical.
The following types of special devices can be used to detect wiring:
- Electromagnetic finders. Appliances react to voltages of at least 1 kW inside the walls. Therefore, in order to find a cable, any electrical appliance is previously included in the outlet. This can be a microwave oven, kettle, hairdryer. At the point where the wiring is located, the device indicator will work.
- Electrostatic finders. They work when checking on the same principle as electromagnetic - they react with a light, sound signal to the passage of current through the cable.
- Metal detector. The device creates an electromagnetic field when approaching metal. The disadvantage of the device is that it reacts to any metal in the wall - fittings, screws, wire. You can correct the situation if you use professional models of devices. They additionally show what type of alloy is hidden behind the wall.
Modern searchers have several functions at the same time - metal search, phase detection, etc. The most popular ones are:
- "Search". Works on the principle of electrostatic cable detection.It can find wiring at a depth of 7 cm. It has four sensitivity modes. The device for detecting wiring in the wall "Search" has a budget price and does not belong to the professional class.
- "Mag-2". This is a combined apparatus that works on the principle of electrostatic or electromagnetic detection. It reacts to the found cable with a sound and light signal. The device can find live and non-live wires.
- LA 1012. This is a more professional device from a Chinese manufacturer. It uses the electromagnetic principle of search.
- BOSH GMS 120. High-precision device from the professional class. Looks for cable in the wall and other metals. Quickly determines the type of alloy.
- Indicator screwdriver or tester. An equally reliable device with which you can determine and even check the performance of a hidden cable. In addition to the fact that the screwdriver can find the "phase" and "zero", find the conductive line, it also indicates the place of the cable break in the wall. To locate the wires, a screwdriver is driven along the panels. In the places of the searched channels, the instrument will show a luminous indication.
It is advisable to load the network when working with a screwdriver.
Alternative search methods
To find the wiring in the wall, without having special equipment, you can use commonplace methods. They are based on simple logic or the use of improvised means. Experienced experts recommend the following:
- Visual inspection of the wall after removing the wallpaper. As a rule, the lines of the location of the strobes differ from the gray concrete walls by the presence of plaster stripes. If all of them are located horizontally and vertically (which is the main condition for laying channels), only at right angles, this is hidden communication.
- Using the radio. To do this, set the frequency to 100 kHz on the device. At these rates, the receiver will respond with an increase in noise to the approaching wiring. You need to drive the machine along the walls, trying to find the lines you are looking for. The same can be done with a cassette recorder or player. You just have to lengthen the wire going to the magnetic head. It will have to be removed from the cassette holder and dotted with wire. The magnetic head here works like an antenna.
- Using a multimeter. It is advisable to add a field-effect transistor to it. Both devices must be connected correctly. The multimeter probes are connected to the drain and source of the transistor without observing the polarities. The device is initially set in ohmmeter mode. A piece of wire should be attached to the shutter, which will act as a search antenna. She needs to be driven along the walls and track the readings on a multimeter. Any changes to them signal the presence of hidden wiring.
- Hearing aid use. This identifier must be set to the "telephone" mode and load the network. The device searches for wiring at a frequency of 50 kHz.
- Compass application. You can use a magnetic device to find out where the wiring runs in the wall. To do this, load the network (for example, turn on the curling iron in the socket) and drive the compass along the wall. Where the arrow begins to deviate, there is a cable.
Using the devices listed above gives quite good results.
Methods that don't work
Some craftsmen, who do not know how to find a wire in a wall, resort to the most absurd methods of finding a cable. These are:
- Application of a magnet. It is believed that if you use (drive along the panels) a single-charged element tied to a thread, it will react to the cable laid in the wall - it will start moving like a pendulum. In brick buildings, this method of finding definitely does not work. In panel ones, the magnet runs the risk of stumbling into just the fittings. When looking for wiring from the side of the ceiling, the method will not work at all. It is not possible to achieve oscillation of the magnet by holding the hanging string horizontally. Gravity interferes.
- Smartphone application.Many models based on Mac or Android OS can allegedly be used as metal detectors. There are even special programs for this. One of the most popular is the "Metall Detector". Its developers assure that with the help of an application and a magnetic sensor built into the device itself, you can safely find a hidden cable. But this is nothing more than a toy that should not be taken too seriously.
When looking for a hidden cable, you should always move from a junction box or outlet.
Logical reasoning
Using standard knowledge of the location of the hidden cable, the technician can safely find the wiring. In this case, it is worth focusing on such norms and schemes:
- From the outlet or switch, the cable always extends upward or towards a larger area of the wall.
- From the floor and ceiling, the cable is always located at 15-20 cm.Therefore, it is not worth looking for a line above / below.
- From gas pipes, batteries, radiators, lines and strobes, according to SNiP, can be hidden at least 40 cm to the sides.
If you have such knowledge, you can supplement them with logic and find the position of the communication in the wall. If the master does not want to take risks, it is better to call the professionals and entrust the work to them.
