A current transformer (CT) is a simple, practical and inexpensive means of detecting the presence of AC current. Detecting load current rather than applied voltage is a superior method of determining ...

This circuit, designed on request, has proven to be useful to indicate when the voltage in a power supply line is changing from 120V to 240Vac. It can be used in different circumstances and circuits, ...

If you’re working with 3.3V or 5V circuits, it’s easy for you to throw on a power or status LED here or there. [Tom Gralewicz] has found himself in a pickle, though, often working on projects with ...