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..




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...

Famous Scientists

Here’s list of some famous scientists. Deliberately short, with the aim to provide a quick memory jog or overview. If your looking for more detailed information...

Cost Performance and Time

Often us engineers get so bogged down in equations, using software, producing drawings and writing specifications that this becomes the sole focus.   ...

The ac resistance of conductors

In a previous article I looked at the dc resistance of conductors and in this article we turn our attention to ac resistance. If you have not read the...

Arc Flash Calculations

Working in the vicinity of electrical equipment poses an hazard. In addition to electric shock hazard, fault currents passing through air causes Arc Flash...

Difference Between Live and Dead Tank Circuit Breakers

A quick post in connection with an email question: Live Tank - the circuit breaker the switching unit is located in an insulator bushing which is live...

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...

Cable Sizing Tool

Our cable sizing tool is one of the more popular tools on the site.  The tool enables cables to be sized in compliance with BS 7671 (the IEE Wiring Regulations...

Are We Losing Professional Integrity

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

Meeting room of the future

The IET site has a video of a visit showing of a high tech meeting room developed at Napier University in Edinburgh. It a good demonstration of innovative...

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