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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

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Magicians of Engineering

The other day I was reading 'Night of the New Magicians' by Mary Pope Osborn with my son. The story is about a young boy and girl who travel back in time...

Gas Insulated or Air Insulated Switchgear

Various arguments exist around SF6 Gas Insulated (GIS) and Air Insulated (AIS) medium voltage switchgear. Recently we had to change a GIS design to AI...

Periodic Electrical Installation Inspection – How Often?

How often installations are inspected is up to the owner of the installation, provided such durations do not exceed any regulatory maximums in force. ...

Lightning Protection and Earth Electrode Resistance

Most installations involve some form of lightning protection system which is connected to an earth electrode. The function of the earth electrode is to...

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...

Star-Delta Motor Starting - Performance

Many questions sent in to the site are in connection with motor starting and in particular star-delta. For all but the simplest application, there is...

Are We Losing Professional Integrity

I have been thinking recently that there appears to be less professional integrity around than when I first started my career in electrical engineering...

Introduction to Traction Substations

Following on from my post on railway electrification voltages, I thought an introduction to traction substations would be a good idea. Traction substations...

Low Voltage Switchroom Design Guide

Low voltage (LV) switchrooms are common across all industries and one of the more common spatial requirements which need to be designed into a project...

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...