From the monthly archives: May 2009

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

UPS Sizing - Rules of Thumb

By Steven McFadyen on 4/30/2009 12:56 AM

It wasn't so long ago I was telling someone that I don't use rules of thumb as most things are easily calculated anyhow.   As it turns out I last week I ended up using what can only be describ... read more..




3 Phase Loads

Three phase systems are derived from three separate windings, either connected in delta or star (wye). Each winding can be treated separately, leading...

Cables for MV Power Distribution - Earthed versus Unearthed Systems

Power cables can basically be classified into earthed and unearthed cables, where earthed and unearthed refer to the application for which the cable is...

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...

Large Hadron Collider

The 27 km, Euro 6 billion  Collider lies on the border between France and Switzerland, took nearly 30 years to complete.  Some of the lofty goals for the...

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...

Lead Acid Batteries

Lead acid batteries are cost effect and reliable, making them suitable for many applications.This note examines topics of interest associated with the...

Cable Insulation Properties

Cable insulation is used to provide electrical separation between conductors of  a cable.  During the historical development of cables, numerous types...

Low Voltage Circuit Breakers

Circuit breakers are switching devices whose primary function is to isolate parts of an electrical distribution system in the even of abnormal conditions...

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...

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...

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