We are pleased to present below all posts archived in 'April 2012'. If you still can't find what you are looking for, try using the search box.
Control theory looks at how systems work and are controlled from a mathematical view. This note gives a brief introduction to some of the concepts – more of a notepad of concepts really, whi... read more..
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 particular ac induction motors. read more..
Variable frequency drives are widely used to control the speed of ac motors. This note looks at the mechanisms which enable d... read more..
Electric motors are one of the most widely used items of electrical equipment. Improving motor efficiency benefits include, reduced power demand, lower operating costs and reduced environment impact.... read more..
Collection of links to various places with useful motor information. I’ll try and return to the page every now and again to update it with any motor notes added to the site. read more..
Insulation on a motor prevents interconnection of windings and the winding to earth. When looking at motors, it is important to understand how the insulation functions and its practical applicatio... read more..
Coils of wire on the rotor carry a d.c. current which generates a magnetic field. A stator magnetic field is created using either permanent mag... read more..
We have had the Wiki with us for a long time now, but at last I have decided to say bye bye – more details on why below. read more..
The windings of many medium and small sized transformers are protected by restricted earth fault (REF) systems. The illustration shows the principal of REF protection. read more..
Electrical notes are a collaborative collection of electrical engineering information and educational material. Any registered user can add content.
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The widely used United Sates standard ANSI/IEEE C37.2 'Electrical Power System Device Function Numbers, Acronyms, and Contact Designations' deals with protective device function numbering and acronyms. ... read more..
Here’s list of some famous scientists. Deliberately short, with the aim to provide a quick memory jog or overview. If your looking for more detailed information, Google and Wikipedia have tons of ... read more..
The other day I was talking to a colleague who is a building services consultant. Despite regularly specifying dry-type/cast resin transformers he was...
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...
HTML supports a variety of entity symbols which can be entered using either numbers or an entity name. The number or name is preceded by the ‘&’ sign...
Carrying out a protection system discrimination study is critical to ensure the correct functioning of the electrical system in the event of faults. ...
Tapping your forearm or hand with a finger could soon be the way you interact with gadgets. A new technology created by Microsoft and Carnegie Mellon ...
How often installations are inspected is up to the owner of the installation, provided such durations do not exceed any regulatory maximums in force. ...
Power cables can basically be classified into earthed and unearthed cables, where earthed and unearthed refer to the application for which the cable is...
It's been a busy few months on different projects or busy couple of decades depending on how I look at it. I can say that on the odd (frequent) occasion...
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...
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...
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