For car enthusiasts, there are multi-purpose measuring devices that are designed specifically for measurements in a car. One such device can measure the crankshaft speed, the angle of the closed state of the breaker contacts, and, in addition, voltage up to 20 volts. The range of resistance measurements by such a device is usually limited to the kilo-ohm region, i.e. 1-1000 kΩ.
In addition, measuring instruments for testing electrical and electronic components are offered. They allow extensive measurements from small resistances in ohms (Ω) to very large resistances in megaohms (MΩ). Voltages (in volts) can be measured very accurately, which is especially required for electronic components.
When it is only necessary to check whether there is voltage in the target at all, a simple test lamp "A" is suitable for this. First of all, it is suitable only for checking electrical circuits in which there are no electronic components. This is due to the fact that electronic components are extremely sensitive to high currents and under certain circumstances can fail already when the test lamp is connected.
Attention: For inspection of electronic components (transistors, diodes, capacitors and control units) a voltage indicator with a high internal resistance "V" is required. It works as a test lamp, but does not cause damage to electronic components and is suitable for all testing work.
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