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

Over the past year or so I've been involved in on going discussions related to referring fault levels from the secondary of a transformer to the primary...

This article gives an introduction to IEEE 485 method for the selection and calculation of battery capacity.

Coils of wire on the rotor carry a d.c. current which generates a magnetic field. A stator magnetic field is created using either permanent magnets or...

Famed English chemist and physicist Michael Faraday was born on September 22, 1791, in Newington Butts, a suburb of Surrey just south of the London Bridge...

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

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...

From the earliest times, humans have found ways to create light. Pre-historic peoples used natural materials (moss, grass, etc.) soaked in animal fat and...

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...

A load flow study is the analysis of an electrical network carried out by an electrical engineer. The purpose is to understand how power flows around...