The windings of many medium and small sized transformers are protected by restricted earth fault (REF) systems. The illustration shows the principal of...

MIT OpenCourseWare, makes the materials used in teaching all MIT subjects available on the Web, free of charge, to any user in the world.

In three phase systems, the use of transformers with three windings (or legs) per side is common.  These three windings are often connected in delta or...

If you are wondering what happened to our cable notes, the short answer is that we have moved them to myCableEngineering.com.  The "Knowledge Base" at...

Laplace transforms and their inverse are a mathematical technique which allows us to solve differential equations, by primarily using algebraic methods...

A battery consists of one or more cells, each of which use stored chemical energy to produce electrical energy, There are many types of cells and these...

This is the first of two posts on the resistance of conductors. In the next post I will look at the ac resistance, including skin effect and we deal with...

Motor starting and its associated problems are well-known to many people who have worked on large industrial processes. However, these things are, of course...

Ever wondered what kind of power an aircraft uses when parked at the airport stand. Normally the aircraft generates it own power, but when parked with...

Various techniques exist to enable the correct selection of batteries for UPS applications.  The procedure described below is one of the more common. ...