From the monthly archives: February 2009

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

Aluminium Windings - Dry Type Transformers

By Steven McFadyen on 2/25/2009 3:19 AM

The other day I was talking to a colleague who is a building services consultant.  Despite regularly specifying dry-type/cast resin transformers he was unaware that many manufactures’ use alu... 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..


Electrical Engineering

By Steven McFadyen on 2/18/2009 9:12 PM

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 early days distributing electrical power. Today, it... 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...

Periodic Electrical Installation Inspection – How Often?

How often installations are inspected is up to the owner of the installation, provided such durations do not exceed any regulatory maximums in force. ...

Tech Topics/Application Notes - Siemens

There are a lot of interesting two page type notes on various medium voltage topics – switchgear, circuit breakers, bus systems etc. It is on the Siemens...

IEEE Winds of Change

IEEE TV has a part series of videos on wind power and it's implication. For a really good overview to the technologies and issues around wind power, these...

IEC 60287 Current Capacity of Cables - Rated Current

In the previous note we looked at the approach taken by the standard to the sizing of cables and illustrated this with an example.  We then looked at one...

Smarter Electrical Distribution

The other day I came across an article in Technology Review on the development of a smart transformer. A professor at North Carolina State University is...

IEC 61439 Verification Methods

The (relatively new) switchgear and control gear standard, IEC 61439 'Low-voltage switchgear and controlgear assemblies' has three methods which can be...

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...

Understanding Motor Duty Rating

One of the comments on my Motor Starting Series was asking for something on duty cycles. Here it is. As a purchaser of a motor, you have responsibility...

Cable Sizing Tool

Our cable sizing tool is one of the more popular tools on the site.  The tool enables cables to be sized in compliance with BS 7671 (the IEE Wiring Regulations...

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