From the monthly archives: January 2013

We are pleased to present below all posts archived in 'January 2013'. If you still can't find what you are looking for, try using the search box.

IEC 60287 Current Capacity of Cables - An Introduction

By Steven McFadyen on 1/31/2013 1:00 PM

IEC 60287 "Calculation of the continuous current rating of cables (100% load factor)" is the International Standard which defines the procedures and equations to be used in determining the ... read more..


Voltage Levels to IEC 60038

By Steven McFadyen on 1/16/2013 10:33 AM

The standard aims to consolidate AC and traction voltages within the industry and defines the following bands:

  • band 1 - A.C. systems 100 V to 1000 V
  • band 2 - A.C and... read more..


DC Component of Asymmetrical Faults

By Steven McFadyen on 1/9/2013 6:52 PM

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 (id.c.).  This initial dc compo... read more..




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...

Introduction to Current Transformers

Current transformers (CTs) are used to convert high level currents to a smaller more reasonable level for use as inputs to protection relays and metering...

Meeting room of the future

The IET site has a video of a visit showing of a high tech meeting room developed at Napier University in Edinburgh. It a good demonstration of innovative...

Write your best report

Years ago I was told that you should always try to write the best report you can.  Many years later I still think on this as one of the better pieces of...

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...

How to Write an Electrical Note

Electrical notes are a collaborative collection of electrical engineering information and educational material. Any registered user can add content. ...

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...

Nikola Tesla

Nikola Tesla was born exactly at midnight on July 10, 1856 in the tiny village of Smiljan, Lika in Croatia. In his late teens, Tesla left the village to...

110 or 230 Volts

I've been considering a blog on the 110 or 230 Volt issue for a while.  While browsing the Internet I came across a great summary by Borat over at  engineering...

E-Ink

Before the technical, some general information. E-ink display are found in a lot of e-readers, some mobile phones and similar devices and the intent is...

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