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..




Occam's Razor

I was reminded of Occam's Razor while reading a book. It's quite a simple principal of logic which has stood the test of time and is accepted as central...

Bows and Arrows

It starts with me reading one of the Horrible History books with my son (Groovy Greeks). Arrows were mentioned which lead to the discussion of the bodkin...

How to Size Current Transformers

The correct sizing of current transformers is required to ensure satisfactory operation of measuring instruments and protection relays. Several methods...

Understanding LV Circuit Breaker Fault Ratings

I think this post is going to be helpful to several of our readers. While the IEC low voltage circuit breaker Standard [IEC 60947-2, Low voltage switchgear...

Welcome back Bottle

‘Kept looking at a card, y’see? Kept looking at it. Welcome back Bottle. Gods below welcome home. The Crippled God A Tale of the Malazan Book of the...

Fault Calculation - Symmetrical Components

For unbalance conditions the calculation of fault currents is more complex. One method of dealing with this is symmetrical components. Using symmetrical...

Alternating Current Circuits

Alternating current (a.c.) is the backbone of modern electrical power distribution. In this article I’ll be pulling some of the more important concepts...

What is Aircraft Ground Power

Ever wondered what kind of power an aircraft uses when parked at the airport stand. Normally the aircraft generates it own power, but when parked with...

Battery Sizing

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

Why use catalogues

I'm a fan of using manufacturers catalogues. There are two main reasons for this. Firstly, if your involved in the purchase of equipment, you will likely...

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