An explanation of the origin of a generator’s subtransient reactance

The term “subtransient reactance” is denoted by the symbol X’’d and is used to calculate available short-circuit generator fault currents. But where does it come from? What’s its origin? Continue reading “An explanation of the origin of a generator’s subtransient reactance”

In-depth explanation of the short-circuit behaviors of five important types of electrical equipment

I described in a previous article the benefits of learning how to do short-circuit analysis by hand. There are five primary elements that you need to know how to model when doing so. I go into the details here . . . . Continue reading “In-depth explanation of the short-circuit behaviors of five important types of electrical equipment”

Calculating short-circuit currents by hand

You won’t do many short-circuit hand calculations, but it’s useful to go through the exercise to develop an understanding of the fault behavior of typical electrical equipment. There are five you should get to know . . . . Continue reading “Calculating short-circuit currents by hand”

Three fault regions of a time-current plot

In a previous article I discussed the importance of coordination curves. Here I provide some home-made examples. Yep, you got it. Fashioned in the fires of Microsoft Powerpoint . . . . Continue reading “Three fault regions of a time-current plot”