From the monthly archives: September 2009

We are pleased to present below all posts archived in 'September 2009'. If you still can't find what you are looking for, try using the search box.

Closed Doors

By Steven McFadyen on 8/28/2009 1:03 AM

"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. If we will only allow that, as we progress, we r... read more..


IEC Reference Designations

By Steven McFadyen on 8/26/2009 11:55 PM

The IEC publishes a series of documents and rules governing the preparation of documents, drawings and the referencing of equipment.   Depending on country and industry, people are either f... read more..


Gas Insulated or Air Insulated Switchgear

By Steven McFadyen on 8/11/2009 2:32 AM

Various arguments exist around SF6 Gas Insulated (GIS) and Air Insulated (AIS) medium voltage switchgear. Recently we had to change a GIS design to AIS due to an instruction from&nbs... read more..


110 or 230 Volts

By Steven McFadyen on 8/2/2009 10:50 PM

I've been considering a blog on the 110 or 230 Volt issue for a while.  While browsing the Internet I came across a great summary by Borat over at  engineering.com.  He ... read more..


Occam's Razor

By Steven McFadyen on 8/2/2009 4:11 AM

I was reminded of Occam's Razor while reading a book. It's quite a simple principal of logic which has stood the test of time and is accepted as central to scientific thought. Without thi... read more..




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 ...

How a Digital Substation Works

Traditionally substations have used circuit breakers, current transformers (CT), voltage transformers (VT) and protection relays all wired together using...

Electromagnetic Compatibility (EMC)

Electromagnetic compatibility (EMC) is the study of coordinating electromagnetic fields give off equipment, with the withstand (compatibility) of other...

Motor Starting - Introduction

Motor starting and its associated problems are well-known to many people who have worked on large industrial processes. However, these things are, of course...

Copyright Infringement

myElectrical does not support or promote the use of copyrighted material without the copyright owner's consent. If you believe that material for which...

Why a Sine Wave?

I received this question by email a few weeks. First thoughts was that it is a product of the mathematics of rotating a straight conductor in a magnetic...

Fault Calculation - Per Unit System

Per unit fault calculations is a method whereby system impedances and quantities are normalised across different voltage levels to a common base.  By removing...

Thermoplastic and Thermosetting Insulation

While there are a vast array of cable insulation materials, these are often divided into two general types; Thermoplastic or Thermosetting. For example...

Random Numbers

Using laser optical pulses the random number generator utilizes the time between arrival of random photos to generate the numbers, ensuring true accuracy...

Post Editing Tips

If you at all familiar with programs like office and outlook, then adding and editing posts is pretty straightforward and intuitive.  However, there are...

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