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..




How to Check a Circuit is Dead

If you want to check a circuit is dead (not live), you should always use the three point method. First check a known live circuit, then check the dead...

Earth Electrode Resistance

Earthing of electrical systems is essential for the correct functioning and the protecting of life and equipment in the event of faults.  The earth electrode...

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...

Cost Performance and Time

Often us engineers get so bogged down in equations, using software, producing drawings and writing specifications that this becomes the sole focus.   ...

How D.C. to A.C. Inverters Work

Traditionally generation of electricity has involved rotating machines to produce alternating sinusoidal voltage and current (a.c. systems). With the development...

Lithium Ion Battery

Over recent years the Lithium Ion battery has become popular in applications requiring high power densities with small weight and footprint.  Today Lithium...

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...

Why use catalogues

I'm a fan of using manufacturers catalogues. There are two main reasons for this. Firstly, if your involved in the purchase of equipment, you will likely...

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...

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...

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