Earthing of electrical systems is essential for the correct functioning and the protecting of life and equipment in the event of faults.  The earth electrode...

While not as popular as it once was, frame leakage protection does still have some use in some circumstances.  In essence frame leakage is an earth fault...

Control theory looks at how systems work and are controlled from a mathematical view.  This note gives a brief introduction to some of the concepts – more...

Over recent years the Lithium Ion battery has become popular in applications requiring high power densities with small weight and footprint.  Today Lithium...

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

When sizing cables nearly, everyone uses some form of software. This ranges from homespun spreadsheets to complex network analyses software. Each has its...

The International System of Units (abbreviated SI) is the world's most widely used system of units.  The system consists of a set of units and prefixes...

This post is quick introduction and overview to different railway electrification voltages used in answer to a question sent in via email. While there...

Multimeters are undoubtedly the most common item of electrical test equipment in use.  Often it is the first piece of equipment people will turn to when...

Many questions sent in to the site are in connection with motor starting and in particular star-delta.  For all but the simplest application, there is...