Fault Calculation - Symmetrical Components

TITLE

For unbalance conditions the calculation of fault currents is more complex. One method of dealing with this is symmetrical components. Using symmetrical components, the unbalance system is broken down in to three separate symmetrical systems:...Read More..

By Steven McFadyen on Wednesday, March 27, 2013

Hazardous Areas – IEC and NEC/CEC Comparison

TITLE

Depending where in the world you work, you are likely following one of two standards International Electrotechnical Commission (IEC) National Electrical Code/Canadian Electrical Code (NEC/CEC) The different nature of the two systems make a direct comparison almost impossible. If you do need to work with......Read More..

By Steven McFadyen on Friday, March 9, 2012

Maxwell's Equations - Gauss's Electric Field Law

TITLE

Gauss's Electrical law defines the relation between charge ("Positive" & "Negative") and electric field.  The law was initially formulated by Carl Friedrich Gauss in 1835. In Gauss's law, the electric field is the electrostatic field.  The law shows how the electrostatic field behaves and varies depending on the charge......Read More..

By Steven McFadyen on Wednesday, September 4, 2013

Community Activity


Journal Entries

Latest Note Discussions

myElectrical Tools

myElectrical Tools

We have tools to help.  Our tools range from assisting with basic calculations to IET compliant cable sizing. Feel free to browse and try. 

Units Conversion
Complex Number Calculator
3-Phase Calculations
BS 7671 Cable Sizing
Circuit Protective Conductor
Power Factor Correction

even more tools...

Contribute

 

Notes

Notes is a collaborative collection of electrical engineering information and educational material. Why not consider adding your knowledge and help make a better Notes for everyone.

Have something interesting to share or some hidden knowledge why not add a post. Sharing your thoughts and ideas is a great way to pass on knowledge.  Who knows you may even become famous along the way. 

Learn More

Contribute - Questions and Answers

Questions

Have a question. Care to help by using your expertise to answer. Contribute to our questions and build up your reputation.

It's quick and easy to ask or answer questions. Why not give it a try.

Learn More


How a Digital Substation Works

Traditionally substations have used circuit breakers, current transformers (CT), voltage transformers (VT) and protection relays all wired together using...

9 power supply issues solved by using a UPS

Installation of a UPS can help in reducing problems due to issues with the power supply.  A lot of people relate this to nine key issues.  Depending on...

The dc resistance of conductors

This is the first of two posts on the resistance of conductors. In the next post I will look at the ac resistance, including skin effect and we deal with...

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 ...

Induction Motor Equivalent Circuit

Induction motors are frequently used in both industrial and domestic applications.  Within the induction motor, an electrical current in the rotor is induced...

Famous Scientists

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...

Alternating Current Circuits

Alternating current (a.c.) is the backbone of modern electrical power distribution. In this article I’ll be pulling some of the more important concepts...

Material Properties

Everything physical in electrical engineering from insulations to conductors revolves around materials. Here we are listing common materials along with...

How Electrical Circuits Work

If you have no idea how electrical circuits work, or what people mean then they talk about volts and amps, hopefully I can shed a bit light.  I’m intending...

Fault Calculation - Per Unit System

Per unit fault calculations is a method whereby system impedances and quantities are normalised across different voltage levels to a common base.  By removing...