From the monthly archives: July 2012

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

Fault Calculations - Typical Equipment Parameters

By Steven McFadyen on 6/24/2012 7:38 AM

A frequent problem in fault calculations is the obtaining of equipment parameters.  While it is always preferable to use the actual parameters of the equipment, sometimes these are not available... read more..


Low Voltage Fault Tables

By Steven McFadyen on 6/24/2012 7:11 AM

The following tables provide quick order of magnitude fault levels for a a range of typical low voltage situations.

read more..


Questions - Reputation and Privilege

By Steven McFadyen on 6/15/2012 9:08 AM

Our question and answer system while letting you do exactly what it says, is much more.  It is a dynamic user driven system, where our users not only ask and answer questions, but can manage the... read more..


Inductance

By Steven McFadyen on 6/3/2012 11:08 AM

When current flows within a wire, a magnetic field is created. The potion of this magnetic field perpendicular to the wire is called the magnetic flux (measured in weber, Wb). Inductance is the ratio... read more..




What are you reading!

Reading is a bit of a hobby of mine and I"ve done a few off-topic posts in the past on this. Rather than continue doing the occasional post I thought ...

What is LED?

Light Emitting Diodes (LED ) are increasing gaining favour in both the domestic and commercial sectors; due to their efficiency, sustainability and durability...

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...

Wiki Depreciation

We have had the Wiki with us for a long time now, but at last I have decided to say bye bye – more details on why below.

Why is electricity so hard to understand?

It's been a busy few months on different projects or busy couple of decades depending on how I look at it. I can say that on the odd (frequent) occasion...

Laplace Transform

Laplace transforms and their inverse are a mathematical technique which allows us to solve differential equations, by primarily using algebraic methods...

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...

Cable Sheath and Armour Loss

When sizing cables, the heat generated  by losses within any sheath or armour need to be evaluated. When significant, it becomes a factor to be considered...

Maxwell's Equations - Introduction

Maxwell's Equations are a set of fundamental relationships, which govern how electric and magnetic fields interact. The equations explain how these fields...

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 ...

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