From the monthly archives: January 2012

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

Switchboard - Forms of Internal Separation

By Steven McFadyen on 1/29/2012 12:57 PM

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

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Railway Electrification Voltages

By Steven McFadyen on 1/23/2012 11:38 AM

This post is quick introduction and overview to different railway electrification voltages used in answer to a question sent in via email. While there are numerous voltages in use through out the w... read more..


What are you reading!

By Steven McFadyen on 1/17/2012 8:49 AM

Reading is a bit of a hobby of mine and I"ve done a few off-topic posts in the past on this. Rather than continue doing the occasional post I thought I would create a master post, where it anyone (... read more..


The ac resistance of conductors

By Steven McFadyen on 1/11/2012 4:03 PM

In a previous article I looked at the dc resistance of conductors and in this article we turn our attention to ac resistance. If you have not read the previous article, now may be a good time to do so. ... read more..


The dc resistance of conductors

By Steven McFadyen on 1/5/2012 2:14 PM

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 this. To get started, this post will look at the... read more..




Large Hadron Collider

The 27 km, Euro 6 billion  Collider lies on the border between France and Switzerland, took nearly 30 years to complete.  Some of the lofty goals for the...

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...

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...

Generator Sizing & Operation Limits

When selecting a generator, there are inherent limits on the active and reactive power which can be delivered. Generators are normally sized for a certain...

A mechanical engineering paper, some history and memories

I was digging in my bookshelf and came across the 80th Anniversary Association of Mine Resident Engineers, Papers and Discussions Commemorative Edition...

MIT OpenCourseWare

MIT OpenCourseWare, makes the materials used in teaching all MIT subjects available on the Web, free of charge, to any user in the world.

IEC 60287 Current Capacity of Cables - An Introduction

IEC 60287 "Calculation of the continuous current rating of cables (100% load factor)" is the International Standard which defines the procedures and equations...

Battery Sizing

This article gives an introduction to IEEE 485 method for the selection and calculation of battery capacity.

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...

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...

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