From the monthly archives: May 2009

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

UPS Sizing - Rules of Thumb

By Steven McFadyen on 4/30/2009 12:56 AM

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 I ended up using what can only be describ... 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...

Differential protection, the good old days

This morning I was explaining how differential protection works to a junior engineer. To give him something to read I opened up the NPAG (Network Protection...

Equipment Verification (to IEC Standards)

One of the requirements to ensuring that everything works is to have equipment selected, manufactured and verified [tested] to IEC standards. Not all equipment...

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...

Fault Calculations - Typical Equipment Parameters

A frequent problem in fault calculations is the obtaining of equipment parameters.  While it is always preferable to use the actual parameters of the equipment...

Back to Basics - Ohm’s Law

Electrical engineering has a multitude of laws and theorems. It is fair to say the Ohm's Law is one of the more widely known; it not the most known. Developed...

Cable Sizing Software

When sizing cables nearly, everyone uses some form of software. This ranges from homespun spreadsheets to complex network analyses software. Each has its...

What is a rectifier transformer?

I've recently come across this question a couple times browsing the internet. Decided to give a quick answer here. A rectifier transformer is a transformer...

Thomas Edison

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...

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 ...

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