myElectrical Home

Fault Calculation - Symmetrical Components

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

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

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

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

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

Aluminium Windings - Dry Type Transformers

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...

EU Code of Conduct on Data Centres - Best Practices

The European Union is implementing a voluntary code of practice for participants with the aim of improving the overall efficiency of data centres. As part...

Nikola Tesla

Nikola Tesla was born exactly at midnight on July 10, 1856 in the tiny village of Smiljan, Lika in Croatia. In his late teens, Tesla left the village to...

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 ...

UPS - Uninterruptible Power Supply

A UPS is an uninterruptible power supply. It is a device which maintains a continuous supply of electrical power, even in the event of failure of the...

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...

Bows and Arrows

It starts with me reading one of the Horrible History books with my son (Groovy Greeks). Arrows were mentioned which lead to the discussion of the bodkin...

Differential protection, the good old days

This morning I was explaining how differential protection works to a junior engineer. To give him something to read I opened up the NPAG (Network Protection...

Battery Sizing

This article gives an introduction to IEEE 485 method for the selection and calculation of battery capacity.

IEC Reference Designations

The IEC publishes a series of documents and rules governing the preparation of documents, drawings and the referencing of equipment. Depending on country...