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


Introduction to Current Transformers

Current transformers (CTs) are used to convert high level currents to a smaller more reasonable level for use as inputs to protection relays and metering...

Paternoster Lifts

These lifts were first built in 1884 by J. E. Hall and called a paternoster ("Our Father", the first two words of the Lord's Prayer in Latin) due to its...

Operational Amplifier

The fundamental component of any analogue computer is the operational amplifier, or op amp. An operational amplifier (often called an op-amp,) is a high...

DC Motor Operation

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 magnets or...

How to Size Current Transformers

The correct sizing of current transformers is required to ensure satisfactory operation of measuring instruments and protection relays. Several methods...

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...

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...

Switchboard - Forms of Internal Separation

IEC 61439 'Low-voltage switchgear and controlgear assemblies', specifies standard arrangements of switchboard (call forms of internal separation). The...

Control Theory

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...

What is a rectifier transformer?

I've recently come across this question a couple times browsing the internet. Decided to give a quick answer here. A rectifier transformer is a transformer...