From the monthly archives: November 2009

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

Lightning Protection and Earth Electrode Resistance

By Steven McFadyen on 11/22/2009 7:48 PM

Most installations involve some form of lightning protection system which is connected to an earth electrode.  The function of the earth electrode is to dissipate the lightning strike safely in to ... read more..


1,000 kV UHV First for China

By Steven McFadyen on 11/3/2009 8:33 PM

At the beginning of the year China put the world's first 1,000 kV UHV transmission system into operation. Transmitting power at over a million volts is just amazing.  Some key facts about the syste... read more..




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...

Large Hadron Collider

The 27 km, Euro 6 billion  Collider lies on the border between France and Switzerland, took nearly 30 years to complete.  Some of the lofty goals for the...

8 Steps to Low Voltage Power Cable Selection and Sizing

A recurring theme on our forums is cable sizing. Now many installations are unique and require special consideration. However, a lot of the time things...

What is an Open Delta Transformer

In three phase systems, the use of transformers with three windings (or legs) per side is common.  These three windings are often connected in delta or...

UPS Sizing - Rules of Thumb

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...

Magicians of Engineering

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...

What happened to the cable notes?

If you are wondering what happened to our cable notes, the short answer is that we have moved them to myCableEngineering.com.  The "Knowledge Base" at...

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...

UPS - Uninterruptible Power Supply

A UPS is an uninterruptible power supply.  It is a device which maintains a continuous supply of electrical power, even in the event of failure of the...

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...

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