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 ...

Power factor correction uses parallel connected capacitors to oppose the effects of inductive elements and reduce the phase shift between the voltage and current. Power factor correction is a ...

Calculations of power and energy are relatively straightforward when the subject is strictly dc circuits. The situation is more complex in the ac world, however. Here are the basics of watts and ...

Two new patented circuits control ac power to resistive and reactive loads with minimal EMI. They are applicable to single and multiple ac phases and varying ac frequencies. Switching ac power on and ...

If you have ever read advanced textbooks or papers about electronics, you may have been surprised to see the use of complex numbers used in the analysis of AC circuits. A complex number has two parts: ...

This is the first of a two-part series on the processes used to find the short circuit current duties of circuit breakers and fuses. In Part 1, we’ll use a simplified power system to illustrate the ...

Both watts (W) and volt-amperes (VA) are units of measurement for electrical power. Watts refer to “real power,” while volt-amperes refer to “apparent power.” Usually, electronic products show one or ...

Recently I mentioned Jay Rosen's complaint about Virgin America: the airline advertises normal 120 volt AC sockets at (most) seats, but Rosen said the power kept being cut off during his flight. I ...

Extension cords are generally a safe solution for running power to electronics that are too far from the nearest wall outlet. But the operative word here is "electronics," which is not as ...