A voltage tester is a device that is used to check and measure the voltage in an electrical circuit. There are different types of testers in the market today. The simplest tester in the form of a screwdriver checks the current that is already in the mains (passive). The multifunctional tester allows you to check de-energized electrical circuits. These devices work in a similar way, but have some differences in the application rules. Some multifunctional testers are equipped with a digital display, indicating the voltage. This will allow you determining the parasitic currents, which are difficult to be detected using the usual indicator. Modern voltage testers are simplified multimeters, but with one sting instead of two probes. Some indicators are even able to measure temperature of the surface. Every device has its advantages and drawbacks. If you still doubt what tester do you need please, feel free to contact our specialists to get all the answers required.