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..




Autonomous Vehicle Challenge

Two driverless and solar power vans have departed from Italy on their way to China via the silk road. During the 13,000 kM trip the vans will drive themselves...

IEC 61439 Verification Methods

The (relatively new) switchgear and control gear standard, IEC 61439 'Low-voltage switchgear and controlgear assemblies' has three methods which can be...

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...

Nikola Tesla

Nikola Tesla was born exactly at midnight on July 10, 1856 in the tiny village of Smiljan, Lika in Croatia. In his late teens, Tesla left the village to...

Why a Sine Wave?

I received this question by email a few weeks. First thoughts was that it is a product of the mathematics of rotating a straight conductor in a magnetic...

Gas Insulated or Air Insulated Switchgear

Various arguments exist around SF6 Gas Insulated (GIS) and Air Insulated (AIS) medium voltage switchgear. Recently we had to change a GIS design to AI...

How to measure power supply quality

If your are ever called out to troubleshoot something on your electrical system, one of the first things consider is the supply voltage. You want to ensure...

Introduction to Current Transformers

Current transformers (CTs) are used to convert high level currents to a smaller more reasonable level for use as inputs to protection relays and metering...

IEEE Winds of Change

IEEE TV has a part series of videos on wind power and it's implication. For a really good overview to the technologies and issues around wind power, these...

Lighting - Lamps

Lamps are the essential part of any luminaire. These are the light generating components. Since the advent of electrical lighting in the middle of the...

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