From the monthly archives: September 2013

We are pleased to present below all posts archived in 'September 2013'. If you still can't find what you are looking for, try using the search box.

Harmonised Cable Codes and Colours

By Steven McFadyen on 8/28/2013 2:17 PM

Within Europe the European Committee for Electrotechnical Standardization (CENELEC) has standardised the both the designation and colour of cables.   These are published in CENELEC document... read more..


UPS - Uninterruptible Power Supply

By Steven McFadyen on 8/21/2013 3:21 PM

A UPS is an uninterruptible power supply.  It is a device which maintains a continuous supply of electrical power, even in the event of failure of the mains (utility) supply.  A UPS is inst... read more..


Cables for MV Power Distribution - Earthed versus Unearthed Systems

By Jeson Pitt on 8/12/2013 12:37 PM

Power cables can basically be classified into earthed and unearthed cables, where earthed and unearthed refer to the application for which the cable is used. Earthed system refers to a three phase syste... 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...

Microsoft OneNote

A couple of months ago I came Microsoft's OneNote and downloaded the 60 day free trail. Since then I have been using it regularly and now have a full license...

Understanding Circuit Breaker Markings

IEC 60947 is the circuit breaker standard and covers the marking of breakers in detail. Any manufacturer following this standard should comply with the...

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...

Robots - Interesting Videos

The robot folding towels post below was interesting enough at the time to post a link.  Recently I’ve come across a couple of other interesting videos...

How to Calculate Motor Starting Time

Request to look at induction motor starting time have come up a few times on the site. Hopefully in this post, I give you guys some idea on how to calculate...

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...

How to refer fault levels across a transformer

Over the past year or so I've been involved in on going discussions related to referring fault levels from the secondary of a transformer to the primary...

The ac resistance of conductors

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...

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...

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