From the monthly archives: April 2009

We are pleased to present below all posts archived in 'April 2009'. If you still can't find what you are looking for, try using the search box.

Software Usage Guidelines

By Steven McFadyen on 3/29/2009 4:41 AM

Using software in our  work is essential for most of us and we are becoming even more dependant on it's use.  While software is a great asset, many times using it can be more problematic ... read more..


Voltage Levels – Confused?

By Steven McFadyen on 3/23/2009 2:06 AM

I was having a conversation the other day about voltage levels.  While everyone was in agreement that low voltage was 1000 V and less, there was more confusion on the terms 'Medium Voltage' and ... read more..


Thomas Edison

By Steven McFadyen on 3/21/2009 10:40 PM

American inventor Thomas Alva Edison was born in Milan, Ohio on February 11, 1847. He was the youngest of seven children and received little formal schooling. Most of his education happened at home unde... read more..


Magicians of Engineering

By Steven McFadyen on 3/15/2009 8:08 PM

The other day I was reading 'Night of the New Magicians' by Mary Pope Osborn with my son.  The story is about a young boy and girl who travel back in time to the 1889 World's Fair in Paris to find ... read more..


Three Phase Current - Simple Calculation

By Steven McFadyen on 3/1/2009 11:47 AM

The calculation of current in a three phase system has been brought up on our site feedback and is a discussion I seem to get involved in every now and again. While some colleagues prefer to remember... read more..




Three Phase Power Simplified

A single phase system is perhaps the most common type of system most people are familiar with. This is what people have in their homes and what appliances...

Cable Sheath and Armour Loss

When sizing cables, the heat generated  by losses within any sheath or armour need to be evaluated. When significant, it becomes a factor to be considered...

HTML Symbol Entities

HTML supports a variety of entity symbols which can be entered using either numbers or an entity name.  The number or name is preceded by the ‘&’ sign...

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...

New Mail Chimp

We've been sending out Newsletters on a regular basis for a few weeks now. To do this we have been using Google's Feedburner service. While Feedburner...

Laplace Transform

Laplace transforms and their inverse are a mathematical technique which allows us to solve differential equations, by primarily using algebraic methods...

Understanding electric motor insulation & temperature

Anyone specifying or using electric motors should have a basic understanding how the insulation is related to temperature. Three classes of insulation...

Introduction to Traction Substations

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

How a Digital Substation Works

Traditionally substations have used circuit breakers, current transformers (CT), voltage transformers (VT) and protection relays all wired together using...

Earth Electrode Resistance

Earthing of electrical systems is essential for the correct functioning and the protecting of life and equipment in the event of faults.  The earth electrode...

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