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..




Photovoltaic (PV) - Utility Power Grid Interface

Photovoltaic (PV) systems are typically more efficient when connected in parallel with a main power gird. During periods when the PV system generates energy...

Low Voltage Fault Tables

The following tables provide quick order of magnitude fault levels for a a range of typical low voltage situations.

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...

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...

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...

Paths of Flight

GE have put together a time-lapse video shown flight take-off and landings at some airports. An interesting view:

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...

Microsoft OneNote

A couple of months ago I came Microsoft's OneNote and downloaded the 60 day free trail. Since then I have been using it regularly and now have a full license...

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...

Harmonised Cable Codes and Colours

Within Europe the European Committee for Electrotechnical Standardization (CENELEC) has standardised the both the designation and colour of cables.   ...

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