From the monthly archives: July 2010

We are pleased to present below all posts archived in 'July 2010'. If you still can't find what you are looking for, try using the search box.

Maximum Demand for Buildings

By Steven McFadyen on 6/16/2010 5:42 PM

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 power results in additional equipment, increased ... read more..


Meeting room of the future

By Steven McFadyen on 6/15/2010 11:05 PM

The IET site has a video of a visit showing of a high tech meeting room developed at Napier University in Edinburgh. It a good demonstration of innovative use of technology, genuinely interesting to wat... read more..




Software Usage Guidelines

Using software in our  work is essential for most of us and we are becoming even more dependant on it's use.  While software is a great asset, many times...

Getting Started with Patents

If you have a great idea or invent something the last thing you want is someone to steal the idea. One of the things you can do is protect the intellectual...

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...

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...

Variable Frequency Drive

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

IEC 61439 - The Switchgear Standard

The new standard IEC 61439 replaces the old 60439. Compared to the old standard, the new 61439 is a more clearly defined and takes into account the assembly...

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...

Introduction to Traction Substations

Following on from my post on railway electrification voltages, I thought an introduction to traction substations would be a good idea. Traction substations...

Three Phase Current - Simple Calculation

The calculation of current in a three phase system has been brought up on our site feedback and is a discussion I seem to get involved in every now and...

DC Motor Operation

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 magnets or...

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