Alternating current (a.c.) is the backbone of modern electrical power distribution. In this article I’ll be pulling some of the more important concepts...

Insulation on a motor prevents interconnection of windings and the winding to earth.  When looking at motors, it is important to understand how the insulation...

The other day I was talking to a colleague who is a building services consultant.  Despite regularly specifying dry-type/cast resin transformers he was...

Years ago I was told that you should always try to write the best report you can.  Many years later I still think on this as one of the better pieces of...

Problems on achieving maximum voltage drop within an installation come up often. Depending where you live, local regulations will have different limits...

Everything physical in electrical engineering from insulations to conductors revolves around materials. Here we are listing common materials along with...

Three phase systems are derived from three separate windings, either connected in delta or star (wye). Each winding can be treated separately, leading...

Following on from my post on railway electrification voltages, I thought an introduction to traction substations would be a good idea. Traction substations...

When selecting a cable, the performance of the cable under fault conditions is an important consideration. It is important that calculations be carried...

Variable frequency drives are widely used to control the speed of ac motors.  This note looks at the mechanisms which enable drive units to control the...