From the monthly archives: April 2012

We are pleased to present below all posts archived in 'April 2012'. If you still can't find what you are looking for, try using the search box.

Control Theory

By Steven McFadyen on 3/29/2012 10:18 PM

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 of a notepad of concepts really, whi... read more..


Useful Motor Technical Information

By Steven McFadyen on 3/28/2012 10:09 PM

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 particular ac induction motors. read more..


Variable Frequency Drive

By Steven McFadyen on 3/28/2012 9:58 PM

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


Motor Efficiency Classification

By Steven McFadyen on 3/28/2012 2:05 PM

Electric motors are one of the most widely used items of electrical equipment. Improving motor efficiency benefits include, reduced power demand, lower operating costs and reduced environment impact.... read more..


Electric Motors

By Steven McFadyen on 3/28/2012 1:12 PM

Collection of links to various places with useful motor information. I’ll try and return to the page every now and again to update it with any motor notes added to the site. read more..


Motor Insulation

By Steven McFadyen on 3/28/2012 1:02 PM

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 functions and its practical applicatio... 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..


Wiki Depreciation

By Steven McFadyen on 3/27/2012 4:06 PM

We have had the Wiki with us for a long time now, but at last I have decided to say bye bye – more details on why below. read more..


Restricted Earth Fault Protection

By Steven McFadyen on 3/25/2012 12:49 PM

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


How to Write an Electrical Note

By Steven McFadyen on 3/24/2012 11:47 AM

Electrical notes are a collaborative collection of electrical engineering information and educational material. Any registered user can add content.

Think of Notes as  an online book;&#... read more..


ANSI (IEEE) Protective Device Numbering

By Steven McFadyen on 3/22/2012 11:40 AM

The widely used United Sates standard ANSI/IEEE C37.2 'Electrical Power System Device Function Numbers, Acronyms, and Contact Designations' deals with protective device function numbering and acronyms. ... 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..


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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...

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...

Electrical Engineering

Electrical engineering is a field that covers a wide variety of sub-fields, including electricity and electronics. It is a field that goes back to the...

Resistors

Resistors are electronic components that oppose the flow of current.  Manufactured in various types and ranges they have a wide application to electronics...

What is Aircraft Ground Power

Ever wondered what kind of power an aircraft uses when parked at the airport stand. Normally the aircraft generates it own power, but when parked with...

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...

Electromechanical Relays

Electromechanical relays have been the traditional backbone of electrical protection systems.  While over recent years these have been replaced by microprocessor...

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...

Laplace Transform

Laplace transforms and their inverse are a mathematical technique which allows us to solve differential equations, by primarily using algebraic methods...

Microsoft OneNote

A couple of months ago I came Microsoft's OneNote and downloaded the 60 day free trail. Since then I have been using it regularly and now have a full license...

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