capable of at least simply showing the presence of potential, even without measuring its effective value.
Vital necessity
A voltage tester is a portable electrical device designed to indicate the presence of potential in conductive areas. In electrical networks, not all wires are dangerous when touched. The current beats those on which there is a phase, but the neutral or ground wire is safe. True, there are reservations.
To understand why you might need a voltage tester at home, it's easiest to give a number of examples. Let's imagine that there was a need for a grinder (grinder), which a neighbor provided for a while. Still used models, the body of which is made of metal. howcheck that the internal circuits are intact, and there is no voltage on the shell? Working with such a tool without first checking it is a very risky undertaking. Or, for example, you need to change a burned-out light bulb in a lamp, the glass bulb of which fell, and only the base remained in the cartridge. Believe the electricians who did the wiring that the switch really breaks the phase wire, and not the zero one, and boldly unscrew the base? Doubtful! There are many such examples. With your own voltage tester, you can always quickly check the electrical installation area. In addition, more complex models allow you to measure the effective value.
Basic Features
The simplest voltage tester is an indicator screwdriver. Inside its transparent case there is a small light bulb that lights up when the sting touches the area under the potential.
How can I check the voltage with a tester? On the upper side of the dielectric handle there is a special metal "penny". To check the section of the circuit, it is necessary to touch the tip of the screwdriver to the conductor being checked, and with your finger to the “penny”. The sting itself cannot be touched. If the phase is present, then the light inside the screwdriver will light up. The second name of such screwdrivers is probes. They are rated up to 250 V.
In addition, some models are equipped with an actual value display.
There are modifications that do not require touching the penny with your finger. You can easily purchase a voltage tester. The instructions for it must be read. This will not only save the device from damage, but also protect the person himself.
Double screwdriver
At the same time, the tool described above is too narrowly specialized. If it is required, for example, to perform the simplest task - phasing, then it turns out to be useless due to the presence of only one pole. In this case, you should pay attention to a more advanced tester - a dual low voltage indicator. Structurally, it can be compared with two screwdrivers connected by a wire. The maximum allowable voltage is 1 kV. Cost - from 100 rubles.
If the bulb inside the case lights up, it will mean that there is voltage in the area. Atthe need to perform phasing, you need to touch one probe to one phase wire, and the other to the other. If the phase on the wires is of the same name, then there will be no indication. Simpler models show the very fact of the presence of a phase, while more complicated ones contain several LEDs on one of the handles, by the glow of which you can determine the voltage value.
"Indicator"
In particular, they can be used to determine the presence of a phase, approximately estimate the voltage level by the glow of the LEDs, and check the conductor for integrity. There is a capacitor inside, which must be pre-charged by touching the probes to 220/380V for 20-30 seconds.
How to find the phase wire
"However, this is not the case. It's just that in a de-energized EMF is induced under the influence of an electromagnetic field. It reaches only a few tens of volts, but is determined by the device and is not a failure in its operation. In such cases, if in doubt, you need to do otherwise: touch one probe to the area being checked, and the other to a known grounded point. If there is a phase on the conductor, the LEDs will light up and show an approximate value of 220 V. By the way, having access to a three-phase voltage, you can check the site by touching not only the "ground", but also other phase wires. That is, the actions are similar to performing phasing. If voltage is present in the section, touching the opposite phase will cause the LEDs to glow at 380 V."
Feature of working with pointer tester
Theoretically, this is a dangerous value (100 mA is lethal), in practice, touching with a hand is possible, however, as long as the internal circuits of the device are working.
Preparing to work with "Contact"
All solutions where two units are wired together are potentially dangerous. One of their disadvantages is the possibility of damage to the connecting conductive core with visible integrity of the sheath. Therefore, when checking the presence of a phase through Ph, it is recommended to use the probe of the block on which this electrode is placed. In this case, the LED will work even if the wire is damaged. However, before taking measurements, you need to connect the device to the mains and hold it for 20 seconds - during this time, the internal energy source will be charged. After that, you need to connect the probes together. If the wire is intact, the “test” LED will light up.
Multipurpose Tool
In addition to all the listed devices, there is another variety - multimeters. Perhaps this is the most advanced voltage tester. How to use it, we will now tell. The cost of the most affordable models starts from 300 rubles. The operating procedure is described in the accompanying instructions, which you need to read. If we talk about checking the voltage, then one wire must be connected to the COM connector, the other to V. Then set the switch to AC 750 mode (alternating current type, limit 750 V) and touch the probes to the "ground" and the area to be tested.
Conclusions
Thus, it is impossible to give an unambiguous recommendation for choosing a device. It all depends on the range of tasks thatplanned to be resolved. If you have extra funds, it is best to purchase a universal multimeter.
