Test light

The colloquially referred to as phase tester conforming to standards as a single-pole voltage tester device is a small, simple test equipment for the detection of AC voltages in the low voltage range from 100 V up to 250 V to ground potential at frequencies between 50 and 500 Hz Typically, it is used for detecting the absence of voltage after the third security rule used in low voltage distribution systems of public power supply.

Types

There are various methods and techniques which can be used in Phase examiners.

Glow lamp

Simple phase tester consist of a small neon lamp and a series resistor in the range from 820 kOhm to 1 M, which are installed in a screwdriver casing and very inexpensive. The tip of the auditor phase is held for the measurement of a conductor to be tested ( for example, a wall outlet ). The other end of the phase auditor is lightly touched with a finger. If the socket contact an outer conductor ("Phase" ), the glow lamp lights up.

The current flowing through the finger contact is typically in the micro-amp range, and is harmless to humans.

Upon contacting the top of the phase checker connected to the neutral conductor or the protective conductor, glow lamp does not light, because their potential to match the ambient potential.

However, one must not rely that a line is de-energized when the glow lamp is not lit, since the current flow of contact resistance depends on the finger and also by the local field conditions. Conversely, it may happen that a voltage appears at an unused conductor when it receives, for example, by the parallel course of a capacitive coupling to an external conductor.

Is the glow lamp also at neutral and / or protective conductor on, there is an error. However, a proper safety ground can not be detected by the phase tester - protective conductor tests require measurement of loop resistance.

For reliable voltage test phase tester are unsuitable, they are therefore also referred to as scammers like phase lies pin, or the like. For a reliable voltage test 2-pole voltage tester shall be used. These devices are also more secure because of the operation, no current flows through the human body. A defective phase tester, such as a faulty resistor, could lead to an electrical accident. The multimeter and installation tester can also measure voltages, but are not voltage tester in the proper sense.

The minimum plausibility check of the phase tester should always be checked by the application on actual measurement object to a live conductor before and. This can at least be ruled out a defective glow lamp.

Non-contact voltage tester

Non-contact voltage tester detected by means of a sensor, the electric field strength in the immediate vicinity of the conductor and optical signal via a display, such as a light emitting diode. For the operation of a battery is required. Depending on the sensitivity can be determined therefore by the insulation of a cable through the existence of voltage.

Non-contact voltage tester is suitable for testing AC voltages, but not for DC voltages.

These devices subject to a separate standard, and in accordance with the basic standards for the design of test and measurement equipment (DIN EN 61010-1; DIN VDE 0411-1 ), they are unsuitable for a reliable voltage test.