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

The following tables provide quick order of magnitude fault levels for a a range of typical low voltage situations.

The image (reproduced from IEC 60909) shows a typical fault in an ac system.  From the illustration it can seen that there is an initial dc component ...

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...

A fundamental concept behind the operation of alternating current systems is that voltage and current waveforms will be sinusoidal – a Sine Wave. This...

Collection of links to various places with useful motor information. I’ll try and return to the page every now and again to update it with any motor notes...

I have been thinking recently that there appears to be less professional integrity around than when I first started my career in electrical engineering...

Most installations involve some form of lightning protection system which is connected to an earth electrode.  The function of the earth electrode is to...

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

In the previous note we looked at the approach taken by the standard to the sizing of cables and illustrated this with an example.  We then looked at one...