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..
ABB has produced a range of technical guides that offer concise explanations of the major technologies and technical issues in low voltage AC drives. ...
MIT OpenCourseWare, makes the materials used in teaching all MIT subjects available on the Web, free of charge, to any user in the world.
Sometimes it’s useful to be able to quickly lookup a piece of technical information. This note is a collection of information related to motors, and in...
Gauss's Electrical law defines the relation between charge ("Positive" & "Negative") and electric field. The law was initially formulated by Carl Friedrich...
The following tables provide quick order of magnitude fault levels for a a range of typical low voltage situations.
IEC 61439 'Low-voltage switchgear and controlgear assemblies', specifies standard arrangements of switchboard (call forms of internal separation). The...
In the previous note we looked at the approach taken by the standard to the sizing of cables and illustrated this with an example. We then looked at one...
Following on from my post on railway electrification voltages, I thought an introduction to traction substations would be a good idea. Traction substations...
One of the comments on my Motor Starting Series was asking for something on duty cycles. Here it is. As a purchaser of a motor, you have responsibility...
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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