From the monthly archives: July 2011

We are pleased to present below all posts archived in 'July 2011'. If you still can't find what you are looking for, try using the search box.

Our internet address and Vanity URLs

By Steven McFadyen on 6/2/2011 5:03 AM

Visitors who like to type web address rather then click menus may be interested in how our URL structure works... read more..




Back to Basics - Ohm’s Law

Electrical engineering has a multitude of laws and theorems. It is fair to say the Ohm's Law is one of the more widely known; it not the most known. Developed...

Battery Sizing

This article gives an introduction to IEEE 485 method for the selection and calculation of battery capacity.

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 ...

UPS Battery Sizing

Various techniques exist to enable the correct selection of batteries for UPS applications.  The procedure described below is one of the more common. ...

Fault Calculation - Symmetrical Components

For unbalance conditions the calculation of fault currents is more complex. One method of dealing with this is symmetrical components. Using symmetrical...

Introduction to Cathodic Protection

If two dissimilar metals are touching and an external conducting path exists, corrosion of one the metals can take place.  Moisture or other materials...

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...

Restricted Earth Fault Protection

The windings of many medium and small sized transformers are protected by restricted earth fault (REF) systems. The illustration shows the principal of...

LED Replacement Light Bulb

The inventor of the first visible light-emitting diode makes history again this year as it begins to show customers a 40-watt replacement GE Energy Smart...

1,000 kV UHV First for China

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...

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