The indicator screwdriver allows you to determine whether the power is connected to a particular wire. To understand the principle of operation of the device, you should be guided in the scheme of electricity supply. In general, all wires located in the house are powered by a switch that supplies current to the apartments.
To get electricity to the outlet, a phase wire is required, which is constantly energized.
The return of the electric current to the circuit breaker is made through a zero wire, which is dangerous only when the device is turned on, the rest of the time it remains unoccupied.
An indicator screwdriver is used to determine the phase wire. Before you start working with the device, you should test it for serviceability. To do this, it is necessary to test the device on a powered source, for example, by inserting its sting alternately into a power outlet. If the light comes on, then everything is in order, otherwise the tool should be replaced. Touching the sting during this process is strictly prohibited!
Indicator screwdriver: principle of operation
The simplest design can only determine the phase contact, and more modern models can detect and zero. There are devices on the market that can find voltage even in hidden wiring (for example, under a layer of plaster), but they have low accuracy.
In appearance, the indicator screwdrivers are practically no different from ordinary screwdrivers, however, in their transparent plastic cases there is a neon bulb that lights up when you touch a live wire, and a small resistor.
In the work of the phase determinant (the second name of the device), one of the links in the chain can be a person. In order for the bulb to light up, you need to attach the tip of the screwdriver to the phase wire and touch the second - zero with your finger. Due to the high resistance of the resistor, the current passing through the human body will be safe and invisible.
The indicator screwdriver allows you to solve several basic problems. Often it is used to test outlet malfunctions. In addition, with the help of the device, the grounding of the extension cord is checked by touching the sting with its tip. If the light does not turn on, then everything is working properly. Using a screwdriver, you can determine the phase in the chandelier holder.
Current should flow through the internal contact, not through the thread. In this case, you should be careful, since touching both contacts simultaneously will cause a short circuit in the network.
In addition, the indicator screwdriver is used when installing sockets and switches, because when installing them, it is important to correctly connect the neutral and phase wires. The tool will help if there is a suspicion that a voltage leak has occurred in any electrical appliance. To fix this fact, you must plug the device into a power outlet and touch the sting with its body. If the bulb does not light up completely, then a small leak still exists. If the indicator is lit at full power, it means that the phase wire is in direct contact with the housing. In both cases, the device must be repaired.