Types of devices present

First, let’s tell you what screwdrivers are and what is the advantage of each type. To date, it is customary to use the following types of indicators:

1. Traditional battery-free probe with flashlight. The principle of operation of such a model is very simple: current flows into the sting, after which it is directed to a resistor, limited and equipped with an indicator light.
   We draw your attention to the fact that on the head of the screwdriver there is a metal nickel, which is the second contact. To check the wires, a person’s finger must be on these nickels, otherwise the probe will not work (the circuit will not close). The advantage of this model is low cost and simple construction. The second advantage is immediately the main disadvantage – the screwdriver without a battery has a minimum set of functions that allows you to find only the phase and zero, or check the voltage at the outlet. You will not succeed in finding a break in the neutral or phase wire with such a tool, because the signal threshold is very high – more than 60 volts.
2. Battery indicator. There is a more advanced version of the probe with a power supply and LED. In appearance, it practically does not differ from the previous model, but if you look inside, you can see the bipolar transistor, which is shown in the diagram below. You can use an indicator screwdriver with a battery for the following types of work: determining phase / zero, plus and minus (in a car), open circuit and location of wires under plaster. The last opportunity allows find the wire in the wall in a non-contact way, but the error can be significant. The advantages of a screwdriver with a battery are that, compared to a conventional probe, such a device can even be used to check the integrity of connectors and fuses, which makes it multifunctional. The battery indicator is best suited for home use.
3. Electronic indicator screwdriver with LCD display. This multifunctional model in addition to including all the functions described above, can also determine the voltage value (in the range from 12 to 220 V). In addition, an electronic indicator can be used to detect hidden wires. In fact, an electronic probe is a miniature version of a multimeter.Due to the fact that its cost is 3-4 times higher than conventional indicators and at the same time does not have as many functions as a full-fledged tester, professional electricians use it very rarely. Self-taught home electricians also do not recommend using this option, because the overpayment will be significant, but not all functions will be used anyway.

So we examined the most popular types of screwdrivers. Next, we will look at how to use each of the models in the most common situations that can occur at home.

Usage tips

At home, an indicator may be needed for the following reasons:

• Find the phase and zero in a socket or lamp;
• Make sure there is voltage in the mains;
• Identification of electrical appliances from which phase breakdown occurs on the housing;
• Check the operation of the electrical extension cord;
• Find the wire in the wall under the tiles or plaster.

Before using the indicator, you need to check it. To do this, it is recommended to check the operation in the energized zone (so we will find out if the indicator light lights up at all). In addition, if the probe is with a battery, you can check as follows: with one finger touch the sting, the other with the nickel and if the light lights up (as shown in the photo), it means that the device is working.

So, see the instructions on how to use the indicator screwdriver correctly in each case

Phase/zero search

The first and most common situation in which you have to use a probe is when you need to find a phase conductor, if at the same time the color marking of the wire is missing. In this case, you need to touch the screwdriver with the sting of the screwdriver. If the light comes on – you have found the phase, no – 0.

When using a regular probe, do not forget to touch it with your finger, otherwise it will not work to determine polarity! If the screwdriver has a battery, there is no need to touch the nickel.

To determine whether there is voltage in the network, simply touch the plugs to the outlets. The LED is on – there is voltage, then no, then no.

Leak detection

The second reason why you need to use a screwdriver at home is when you need to find out where the leakage current occurs and in other words, the breakdown of the body of the electrical device. In this case, both the regular probe and the electronic version can cope with the problem. The use in this case is simple – you need to bring the sting to the ground antenna in one of the ports. If the LED light comes on, there is a leak.

Then you need to act by the exclusion method, namely:

• Disconnect all electrical appliances from the network;
• Turn each device on in turn and check for leaks;
• The lamp does not light up – the equipment is running, it lights up – there is a leak on the running equipment.

We immediately recommend that you familiarize yourself with similar materials – Reasons for turning on the RCD because In the event of a leak, this type of automation turns on immediately, as a result of which the electricity in the house is turned off. If the indicator lights up at zero, then the neutral conductor has burned out and you have two phases in the wiring. This is very serious and you need to go straight to troubleshooting. We advise you to immediately see the consequences of cutting zero on the power grid to see how dangerous it is.

Looking for wire cutters

If electricity does not go to the outlets and electrical appliances in the room, but there is power at the input, you can try to determine the wire break using a screwdriver. Of course, the probe will not show where the well-hidden wires are damaged, but, nevertheless, the electronic device will be able to detect an approximate fracture zone. To do this, based on the wiring diagram in the house, make a bite in the place where the cable is located in the wall from the junction box to the outlet.When a break occurs, the light should stop burning.

The second search method is to scan the entire line. In this case, you will not be able to pinpoint exactly the indicator at which the connection break occurs, but you can at least be sure of its existence. By the way, in this case, you can use even the simplest screwdriver with a battery. All that is required is to cut off the power supply to the shield, take an exposed wire in one hand, and touch the probe with the sting of the second core. In this way, a closed circuit is formed and if there is already a break, the bulb should not light.

I immediately draw your attention to the fact that it is necessary to check the hole when the lamp is with the power off, but the light switch is on. If you forget to close the circuit on the switch, the screwdriver indicator will show that the circuit is broken, but this does not mean that there is an open slot!

Immediately I would like to add one more situation, which is often found in everyday life. To check whether the lamp is working, you need to take it with your fingers on the base and touch the sting on the central contact. In this case, the finger should be on top of the pen. If the indicator light in the handle lights up, the lamp itself is working!

Check the extension cord

Well, the last point I want to focus on is knowing how to properly use a screwdriver when inspecting an electrical extension cord. Things are a little more complicated here, so take a closer look at the material below.

First you need to disconnect the “load” from the network and other electrical appliances. Next, you need to make a connection from the wire and insert it between the sockets of one of the sockets of the unit (short circuit). Further, everything is very simple – you need to take one of the conducting electrodes with your finger, and touch the second with the tip of the probe. The result is determined as always – the indicator light is on, so everything works, no, respectively, no.

After checking, be sure to pull the jumper out of the plugs, otherwise when connecting the carrying case, there will be a short circuit in the power supply. If the indicator indicates that the product is not working, we recommend doing it yourself electrical extension cord and not repairing the old one!

So we have sorted out all the most common cases in which you need to know how to use a screwdriver with a battery and without a power supply. We hope you now understand the principle of the probe and the situations in which you can use it.