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..
The following tables provide quick order of magnitude fault levels for a a range of typical low voltage situations.
I was digging in my bookshelf and came across the 80th Anniversary Association of Mine Resident Engineers, Papers and Discussions Commemorative Edition...
Most installations involve some form of lightning protection system which is connected to an earth electrode. The function of the earth electrode is to...
When sizing cables nearly, everyone uses some form of software. This ranges from homespun spreadsheets to complex network analyses software. Each has its...
One of the requirements to ensuring that everything works is to have equipment selected, manufactured and verified [tested] to IEC standards. Not all equipment...
Variable frequency drives are widely used to control the speed of ac motors. This note looks at the mechanisms which enable drive units to control the...
If you want to check a circuit is dead (not live), you should always use the three point method. First check a known live circuit, then check the dead...
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...
While not as popular as it once was, frame leakage protection does still have some use in some circumstances. In essence frame leakage is an earth fault...
A quick post in connection with an email question: Live Tank - the circuit breaker the switching unit is located in an insulator bushing which is live...
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