DC Component of Asymmetrical Faults
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 ...
Tips for a better Low Voltage Protection Discrimination Study
Carrying out a protection system discrimination study is critical to ensure the correct functioning of the electrical system in the event of faults. ...
Microsoft OneNote
A couple of months ago I came Microsoft's OneNote and downloaded the 60 day free trail. Since then I have been using it regularly and now have a full license...
Why a Sine Wave?
I received this question by email a few weeks. First thoughts was that it is a product of the mathematics of rotating a straight conductor in a magnetic...
Power Transformers - An Introduction
One of the fundamental requirements of an alternating current distribution systems it to have the ability to change the magnitude of voltages. It is more...
Cable Insulation Properties
Cable insulation is used to provide electrical separation between conductors of a cable. During the historical development of cables, numerous types...
IEC 60287 Current Capacity of Cables - An Introduction
IEC 60287 "Calculation of the continuous current rating of cables (100% load factor)" is the International Standard which defines the procedures and equations...
Useful Motor Technical Information
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...
MIT OpenCourseWare
MIT OpenCourseWare, makes the materials used in teaching all MIT subjects available on the Web, free of charge, to any user in the world.
Batteries
A battery consists of one or more cells, each of which use stored chemical energy to produce electrical energy, There are many types of cells and these...