A continuity tester is straightforward equipment having a couple of checking prods and a light (LED) or buzzer alarm. It is utilized to sense the existence of continuity or a break across the two ends of a metal wire which is joined to its checking prods.
For example, if the probes of a continuity tester are contacted to the two ends of a wire roll, its signal (LED) may get triggered to assure that there is no break in the conduction of the link and the wire is fine, or, if the indicator exhibits neutral indications, it would mean that there’sa cut in the continuity of the conductor and requires observation.
How to make a simple continuity tester can be understood in a better way by refering the CIRCUIT DIAGRAM provided through the link.
It may also be incorporated to track out trouble in complex electronic printed circuit boards, car electrical etc.. Since it itself functions at a very nominal voltage and generates a very strong resistance across its probes, the chances of the sophisticated PCB parts getting burnt are nullified. It is always imperative to switch OFF the voltage of the circuit under investigation, otherwise the tester might get triggered through the potential of the circuit and produce wrong indications.