Maxwell's Equations - Introduction
Maxwell's Equations are a set of fundamental relationships, which govern how electric and magnetic fields interact. The equations explain how these fields...
Nikola Tesla
Nikola Tesla was born exactly at midnight on July 10, 1856 in the tiny village of Smiljan, Lika in Croatia. In his late teens, Tesla left the village to...
myElectrical - Cable Sizing Tool Upgrade
Our IEE cable sizing was wrote a few years ago and had become rough around the edges. I thought it was time to give the tool a service. Unfortunately when...
Lithium Ion Battery
Over recent years the Lithium Ion battery has become popular in applications requiring high power densities with small weight and footprint. Today Lithium...
IEC 60287 Current Capacity of Cables - Rated Current
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...
Lighting - Lamps
Lamps are the essential part of any luminaire. These are the light generating components. Since the advent of electrical lighting in the middle of the...
RLC Circuit, Resistor Power Loss - some Modelica experiments
Modelica is an open source (free) software language for modelling complex systems. Having never used it before, I thought I would download a development...
Variable Frequency Drive
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...
UPS Sizing - Rules of Thumb
It wasn't so long ago I was telling someone that I don't use rules of thumb as most things are easily calculated anyhow. As it turns out I last week...
Restricted Earth Fault Protection
The windings of many medium and small sized transformers are protected by restricted earth fault (REF) systems. The illustration shows the principal of...