From the monthly archives: August 2012

We are pleased to present below all posts archived in 'August 2012'. If you still can't find what you are looking for, try using the search box.

Electromagnetic Compatibility (EMC)

By Steven McFadyen on 7/10/2012 4:23 PM

Electromagnetic compatibility (EMC) is the study of coordinating electromagnetic fields give off equipment, with the withstand (compatibility) of other equipment within the vicinity. In it's simplest... read more..


Power Factor

By Steven McFadyen on 7/10/2012 11:43 AM

Power factor is the ratio between the real power (P in kW) and apparent power (S in kVA) drawn by an electrical load.

The reactive power (Q in kVAr) causes the real and apparent power to be ... read more..


Resistors

By Steven McFadyen on 7/9/2012 10:48 AM

Resistors are electronic components that oppose the flow of current.  Manufactured in various types and ranges they have a wide application to electronics. 

read more..


9 power supply issues solved by using a UPS

By Steven McFadyen on 7/3/2012 1:58 PM

Installation of a UPS can help in reducing problems due to issues with the power supply.  A lot of people relate this to nine key issues.  Depending on the type of UPS installed it is possible... read more..


Fault Calculations - Introduction

By Steven McFadyen on 7/1/2012 10:45 AM

Fault calculations are one of the most common types of calculation carried out during the design and analysis of electrical systems. These calculations involve determining the current flowing through... read more..




DC Component of Asymmetrical Faults

The image (reproduced from IEC 60909) shows a typical fault in an ac system.  From the illustration it can seen that there is an initial dc component ...

Motor Starting - Introduction

Motor starting and its associated problems are well-known to many people who have worked on large industrial processes. However, these things are, of course...

Lightning Risk Assessment (IEC 62305)

IEC 62305 'Protection against lightning' requires a risk assessment be carried out to determine the characteristics of any lightning protection system...

Why a Sine Wave?

I received this question by email a few weeks. First thoughts was that it is a product of the mathematics of rotating a straight conductor in a magnetic...

What is a rectifier transformer?

I've recently come across this question a couple times browsing the internet. Decided to give a quick answer here. A rectifier transformer is a transformer...

GE's Shingijutsu Factory

GE's latest thinking on product manufacturing is he Shingijutsu philosophy or Lean production system. They have started applying this at the Louisville...

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...

Understanding LV Circuit Breaker Fault Ratings

I think this post is going to be helpful to several of our readers. While the IEC low voltage circuit breaker Standard [IEC 60947-2, Low voltage switchgear...

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...

Generation of a Sine Wave

A fundamental concept behind the operation of alternating current systems is that voltage and current waveforms will be sinusoidal – a Sine Wave. This...

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