Generation of a Sine Wave

By Steven McFadyen on 4/16/2012 1:57 PM

A fundamental concept behind the operation of alternating current systems is that voltage and current waveforms will be sinusoidal – a Sine Wave. This is best explained by considering how a coil of wire... read more..


Michael Faraday (the father of electrical engineering)

By Steven McFadyen on 2/22/2009 8:22 PM

Famed English chemist and physicist Michael Faraday was born on September 22, 1791, in Newington Butts, a suburb of Surrey just south of the London Bridge. His family was not very well off and could onl... read more..


Lithium Ion Battery

By Steven McFadyen on 11/11/2012 11:46 AM

Over recent years the Lithium Ion battery has become popular in applications requiring high power densities with small weight and footprint.  Today Lithium Ion batteries are commonly found in mobil... read more..


Low Voltage Fault Tables

By Steven McFadyen on 6/24/2012 7:11 AM

The following tables provide quick order of magnitude fault levels for a a range of typical low voltage situations.

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9 power supply issues solved by using a UPS

By Steven McFadyen on 7/3/2012 1:58 PM

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 type of UPS installed it is possible... read more..


IEC 61439 Verification Methods

By Steven McFadyen on 3/3/2012 3:33 PM

The (relatively new) switchgear and control gear standard, IEC 61439 'Low-voltage switchgear and controlgear assemblies' has three methods which can be used to verify the characteristics of an assemb... read more..


8 Steps to Low Voltage Power Cable Selection and Sizing

By Steven McFadyen on 7/25/2011 2:48 AM

A recurring theme on our forums is cable sizing. Now many installations are unique and require special consideration. However, a lot of the time things are just repeated. When looking at low voltage pow... read more..


Questions - Reputation and Privilege

By Steven McFadyen on 6/15/2012 9:08 AM

Our question and answer system while letting you do exactly what it says, is much more.  It is a dynamic user driven system, where our users not only ask and answer questions, but can manage the... read more..


Famous Scientists

By Steven McFadyen on 3/22/2012 11:35 AM

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, Google and Wikipedia have tons of ... read more..


Material Properties

By Steven McFadyen on 5/10/2012 2:15 PM

Everything physical in electrical engineering from insulations to conductors revolves around materials. Here we are listing common materials along with their most useful properties in relation to electr... read more..


Surface Treatment – Ladders, Trays and Baskets

By Steven McFadyen on 5/22/2012 8:41 AM

Steel ladders, trays and baskets form the backbone of cable containment systems. Often these items need some form of surface treatment to prevent corrosion due to the installed environmental conditio... read more..


DC Motor Operation

By Steven McFadyen on 3/28/2012 1:00 PM

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 mag... read more..




Motor Insulation

Insulation on a motor prevents interconnection of windings and the winding to earth.  When looking at motors, it is important to understand how the insulation...

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...

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 ...

Restricted Earth Fault Protection

The windings of many medium and small sized transformers are protected by restricted earth fault (REF) systems. The illustration shows the principal of...

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...

Low Voltage Circuit Breakers

Circuit breakers are switching devices whose primary function is to isolate parts of an electrical distribution system in the even of abnormal conditions...

Multimeter

Multimeters are undoubtedly the most common item of electrical test equipment in use.  Often it is the first piece of equipment people will turn to when...

Closed Doors

"I can live with doubt and uncertainty and not knowing. I think it is much more interesting to live not knowing than to have answers that might be wrong...

Skin Tapping Input

Tapping your forearm or hand with a finger could soon be the way you interact with gadgets. A new technology created by Microsoft and Carnegie Mellon ...

Variable Frequency Drive

Variable frequency drives are widely used to control the speed of ac motors.  This note looks at the mechanisms which enable drive units to control the...

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