From the monthly archives: October 2013

We are pleased to present below all posts archived in 'October 2013'. If you still can't find what you are looking for, try using the search box.

What is LED?

By Dan Ryan on 9/14/2013 8:06 AM

Light Emitting Diodes (LED ) are increasing gaining favour in both the domestic and commercial sectors; due to their efficiency, sustainability and durability.  LED are semiconductor devi... read more..


Maxwell's Equations - Gauss's Electric Field Law

By Steven McFadyen on 9/4/2013 3:47 PM

Gauss's Electrical law defines the relation between charge ("Positive" & "Negative") and electric field.  The law was initially formulated by Carl Friedrich Gauss in 1835.

In Gauss'... read more..


Maxwell's Equations - Introduction

By Steven McFadyen on 9/4/2013 2:33 PM

Maxwell's Equations are a set of fundamental relationships, which govern how electric and magnetic fields interact. The equations explain how these fields are generated and interact with each other, ... read more..




UPS Battery Sizing

Various techniques exist to enable the correct selection of batteries for UPS applications.  The procedure described below is one of the more common. ...

MIT OpenCourseWare

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

Power Factor

Power factor is the ratio between the real power (P in kW) and apparent power (S in kVA) drawn by an electrical load. The reactive power (Q in kVAr)...

Always Use PPE

A lot of our members work in countries where PPE (personal protective equipment) is regulated or they work for companies/organizations which take employee...

DC Component of Asymmetrical Faults

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 ...

Railway Electrification Voltages

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

Closed Doors

"I can live with doubt and uncertainty and not knowing. I think it is much more interesting to live not knowing than to have answers that might be wrong...

Sony Pocket eBook Reader

For the past few years I have reading eBooks on my HTC touch phone. On and off I have debated buying an eReader and recently purchased a Sony PRS-300 ...

Introduction to Cathodic Protection

If two dissimilar metals are touching and an external conducting path exists, corrosion of one the metals can take place.  Moisture or other materials...

Dielectric loss in cables

Dielectrics (insulating materials for example) when subjected to a varying electric field, will have some energy loss.   The varying electric field causes...

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