For electricity to flow, everything needs to be connected in a big ring. It’s called a circuit. For example, the lights in most houses and flats are part of a circuit controlled by the consumer unit, ...

Editor's Note: Here's another take on the transformerless AC line power supply, which finds use in some well-insulated, low-power devices. Our technical reviewer pointed out that C ac should be an ...

Inductance is the link between electric circuits and magnetic fields. Voltage and current sine waves are in-phase when they peak and cross the zero axis at the same time. However, this rarely happens ...

Switching ac power on and off has been a challenge since Edison and others started switching power more than 125 years ago. Now, a solid-state relay (SSR) uses a patented zero-voltage crossing ...