We are pleased to present below all posts archived in 'April 2009'. If you still can't find what you are looking for, try using the search box.
Using software in our work is essential for most of us and we are becoming even more dependant on it's use. While software is a great asset, many times using it can be more problematic ... read more..
I was having a conversation the other day about voltage levels. While everyone was in agreement that low voltage was 1000 V and less, there was more confusion on the terms 'Medium Voltage' and ... read more..
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. Most of his education happened at home unde... read more..
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 to the 1889 World's Fair in Paris to find ... read more..
The calculation of current in a three phase system has been brought up on our site feedback and is a discussion I seem to get involved in every now and again. While some colleagues prefer to remember... read more..
There are a lot of interesting two page type notes on various medium voltage topics – switchgear, circuit breakers, bus systems etc. It is on the Siemens...
The new standard IEC 61439 replaces the old 60439. Compared to the old standard, the new 61439 is a more clearly defined and takes into account the assembly...
In a previous article I looked at the dc resistance of conductors and in this article we turn our attention to ac resistance. If you have not read the...
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...
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...
Traditionally generation of electricity has involved rotating machines to produce alternating sinusoidal voltage and current (a.c. systems). With the development...
Working in the vicinity of electrical equipment poses an hazard. In addition to electric shock hazard, fault currents passing through air causes Arc Flash...
The European Union is implementing a voluntary code of practice for participants with the aim of improving the overall efficiency of data centres. As part...
MIT OpenCourseWare, makes the materials used in teaching all MIT subjects available on the Web, free of charge, to any user in the world.
Gauss's Electrical law defines the relation between charge ("Positive" & "Negative") and electric field. The law was initially formulated by Carl Friedrich...
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