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).

read more..


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..




Electromagnetic Fields - Exposure Limits

Exposure to time varying magnetic fields, from power frequencies to the gigahertz range can have harmful consequences.  A lot of research has been conducted...

Tips for a better Low Voltage Protection Discrimination Study

Carrying out a protection system discrimination study is critical to ensure the correct functioning of  the electrical system in the event of faults. ...

Motor Efficiency Classification

Electric motors are one of the most widely used items of electrical equipment. Improving motor efficiency benefits include, reduced power demand, lower...

Capacitors - Energy Storage Application

Capacitors have numerous applications in electrical and electronic applications.  This note examines the use of capacitors to store electrical energy....

Frame Leakage Protection

While not as popular as it once was, frame leakage protection does still have some use in some circumstances.  In essence frame leakage is an earth fault...

Cold Fusion (or not?)

Recently I have seen a few interesting articles on viable cold fusion; the combining of atoms at room like temperatures to create boundless energy. Now...

Voltage Drop in Installations - Concepts

Problems on achieving maximum voltage drop within an installation come up often. Depending where you live, local regulations will have different limits...

Introduction to Current Transformers

Current transformers (CTs) are used to convert high level currents to a smaller more reasonable level for use as inputs to protection relays and metering...

Maximum Demand for Buildings

Estimating maximum demand is a topic frequently discussed. Working out how much power to allow for a building can be very subjective . Allowing too much...

Laplace Transform

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

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