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.
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..
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..
Dielectrics (insulating materials for example) when subjected to a varying electric field, will have some energy loss. The varying electric field causes...
The mobile phone was born in 1973. They were the size of a brick and weighed a couple of kg, making them difficult to fit into your pocket. At a few thousand...
When looking at the design of a lighting scheme it is useful to have an understanding on the nature of light itself and some of the basic theory associated...
The standard aims to consolidate AC and traction voltages within the industry and defines the following bands: band 1 - A.C. systems 100 V to 1...
IEC 60287 "Calculation of the continuous current rating of cables (100% load factor)" is the International Standard which defines the procedures and equations...
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...
Our IEE cable sizing was wrote a few years ago and had become rough around the edges. I thought it was time to give the tool a service. Unfortunately when...
The image (reproduced from IEC 60909) shows a typical fault in an ac system. From the illustration it can seen that there is an initial dc component ...
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...
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