From the monthly archives: November 2009

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

Lightning Protection and Earth Electrode Resistance

By Steven McFadyen on 11/22/2009 7:48 PM

Most installations involve some form of lightning protection system which is connected to an earth electrode.  The function of the earth electrode is to dissipate the lightning strike safely in to ... read more..


1,000 kV UHV First for China

By Steven McFadyen on 11/3/2009 8:33 PM

At the beginning of the year China put the world's first 1,000 kV UHV transmission system into operation. Transmitting power at over a million volts is just amazing.  Some key facts about the syste... read more..




Switchboard - Forms of Internal Separation

IEC 61439 'Low-voltage switchgear and controlgear assemblies', specifies standard arrangements of switchboard (call forms of internal separation). 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...

Fault Calculation - Per Unit System

Per unit fault calculations is a method whereby system impedances and quantities are normalised across different voltage levels to a common base.  By removing...

Photovoltaic (PV) Panel - Performance Modelling

In an earlier note on the site [Photovoltaic (PV) - Electrical Calculations], the theory of solar (PV) cell calculations was introduced.  In particular...

Questions - Reputation and Privilege

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...

Always Use PPE

A lot of our members work in countries where PPE (personal protective equipment) is regulated or they work for companies/organizations which take employee...

Fault Calculations - Introduction

Fault calculations are one of the most common types of calculation carried out during the design and analysis of electrical systems. These calculations...

What happened to the cable notes?

If you are wondering what happened to our cable notes, the short answer is that we have moved them to myCableEngineering.com.  The "Knowledge Base" at...

Electromagnetic Compatibility (EMC)

Electromagnetic compatibility (EMC) is the study of coordinating electromagnetic fields give off equipment, with the withstand (compatibility) of other...

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...

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