How to choose a hidden wire detector

Today we will talk about hidden wiring detectors, what they are, how to choose such a device and how to work with it correctly.

Purpose of concealed wiring detectors

Carrying out repair work in premises that were built a long time ago, and there are no accompanying documents for the premises, in particular, electrical wiring diagrams, are significantly complicated.

After all, if you need to drill walls, there is a possibility of getting into the wiring.

And this is life-threatening, especially if the wiring is not de-energized, you can damage the tool or the wire itself, which is even worse, since you will have to pull the wiring again.

In general, without knowing the exact location of the wiring, doing something with the walls of the building is more expensive for yourself.

Special devices can come to the rescue - hidden wiring detectors, they are also indicators, which are one of the main ones.

The main task of such a device is to detect wires hidden from the eyes in order to avoid getting into it and damaging it in the future.

The devices themselves are quite compact and portable. To determine the hidden wire, it is enough to run the device along the wall, in the place where the wiring is laid - it will signal. Everything is simple and convenient.

In addition to the main function, some models of detectors can perform a number of additional functions that can make life much easier.

This device will be useful primarily for electricians, because they often have to carry out repair work with wiring in buildings. It is also useful for those who are engaged in mounting something on the walls in the premises.

Types of detectors, their features

Now hidden wire detectors are being produced, the design of which affects the way the wire is detected, and also affects the conditions for detection.

One of the types of this device is electrostatic indicators.

They use sensors that are sensitive to an electrostatic field to detect wiring.

They are among the cheapest, although their detection accuracy is very good - up to 1 cm from the axis of the wire, that is, it is able to almost accurately detect the wire.

The depth of the wire, which is able to detect an electrostatic detector, reaches 60 mm, which is also quite good.

However, it can only detect wires that are energized, which is one of its drawbacks.

In addition, this device will not work if the wall is wet or covered with metal. But in general, it is quite suitable for finding wiring in an apartment.

The second type of detectors is electromagnetic.

In them, sensors respond to an electromagnetic field.

They are also quite accurate and detect wiring even at great depths.

He is not "afraid" of damp walls and their metal coating. But they, too, can only detect wiring that is powered.

At the same time, for its operation, it is necessary that the wires are loaded, therefore, to detect the wiring, a consumer with a power of at least 1 kW should be connected to it.

And the third kind.

Nothing more than ordinary metal detectors, but only very compact ones.

Structurally, it differs from the previous two.

The first two use sensors that respond to the field that creates around itself an electric current passing through the wiring.

The metal detector, on the other hand, consists of a coil that creates an electromagnetic field around itself.

If any metal object gets into this field, this will change the field of the device, to which it will react.

Metal detectors are able to detect metal hidden in the wall. Moreover, some high-tech devices are able to determine what metal he found - black or non-ferrous, to detect changes in the environment inside the wall (voids), even to indicate hidden wooden or plastic elements.

One of its main drawbacks is that it will not react to the voltage in the wiring, that is, it will show that there is metal inside, but whether it is wiring and whether voltage passes through it - no.

Each of these types has its drawbacks, and in order to eliminate them, manufacturers are increasingly producing combined devices that include all detection methods.

They are now the most common.

Primary and secondary functions

The main functions of these devices are:

• Detection of voltage in the wiring in a non-contact way;
• Detection of electromagnetic field in live wires;
• Checking the integrity of the wiring;
• Identification of the polarity of networks with direct current.

And these are not all the primary functions that an indicator can have.

The number of them depends on the design features of the device itself.

Also, a modern combined hidden wiring detector is capable of:

• Identify wood and plastic inserts in the walls;
• Reveal voids;
• Detect all metal elements in the wall, even small ones;
• Determine the depth of occurrence of all detected elements.

All this makes it possible to draw up a complete map of the wall before carrying out repair or other work.

Such a device has quite enough positive qualities, but not all models are equipped with them, so when choosing, you need to take into account some of the nuances:

• You should immediately determine the functionality of the device. If you only need to detect wiring, it is enough to purchase a simple detector, perhaps even of a certain type, and not a combined one;
• In the selection process, you need to conduct a full check of the device's performance. To do this, you first need to check it on an open powered wiring, then already - check it on the wall;
• It is necessary to look at its characteristics in the technical documentation for the device and, in the process of checking, find out whether they coincide with the declared ones;
• If the device is simple and not equipped with a display, you should pay attention to the alarm when wiring is detected - it should be clearly visible, and sound signals should be clearly audible;
• Ask about quality certificates, the original device of a good manufacturer will always come with accompanying documentation.

Main characteristics of detectors

As for the characteristics of these devices, which should be considered when choosing, the main one is the depth of detection.

But before that, you need to ask what he will generally react to.

For example, a combined instrument is able to detect ferrous metal (steel, cast iron) at a depth of up to 120 mm, copper - at a depth of up to 80 mm, wood - up to 38 mm, wiring that is energized - up to 50 mm.

But another device is not designed to detect wood, but metals and wiring can be detected.

At the same time, it will detect ferrous metal at a depth of up to 50 mm, copper - up to 25 mm, and live wiring - up to 50 mm.

In general, other characteristics, such as the temperature range in which the detector can be used, the way it is powered can be classified as secondary, because they do not affect the use of a special role.

Let's talk a little about the instructions for using these devices.

It should be borne in mind that each type of device has different conditions of use.

So, an electrostatic detector can only detect live wires, so you first need to check if it is on the network.

Then you need to check the alarm of this device. To do this, you need to bring it to a non-hidden wire.

The simplest devices are usually equipped only with a sound alarm with a changing tone. When as close as possible to the wire, you need to remember the tone of the sound, after which you can start searching for hidden wiring.

It is better to take a pencil or pen with you right away to make notes on the wire.

It is somewhat easier to work with an electromagnetic detector. Any checks of the device itself are not needed, but the preparatory work will be needed.

They come down to connecting to the network of a consumer with a power of 1 kW.

The easiest to use are combined appliances.

Usually, they have control keys on the detector panel that allow you to select the material that will be searched in the wall, that is, it is enough to press the required key and the device will respond to the selected material.

For example, the same one on the front panel has material selection keys - wood, metal, live wiring.

At the same time, more detailed information will be displayed on its display when something is found in the wall.

And yet, before starting work on the study of the wall, you still need to check the charge of the battery from which the device is powered. The more the battery is discharged, the worse the device will detect.

Homemade appliances

Finally, I would like to mention that some radio amateurs make a detector for detecting hidden wiring with their own hands, and some circuits of these devices are not particularly complicated.

The simplest device for detecting hidden wiring consists of just a field effect transistor and operating in ohmmeter mode.

The transistor connected to the multimeter is driven along the surface of the wall, in the place of the greatest deviation of the multimeter indicators, the wiring will be located.

It should be pointed out that only a network under voltage can be detected in this way.

In addition, there are still quite a few hidden wiring indicator circuits that you can assemble yourself with at least a little knowledge in radio electronics.

So it is not necessary to purchase a device, especially if you need it only for a one-time use.

THIS MAY BE INTERESTING: