From the monthly archives: October 2011

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

Tip – Latitude and Longitude on Large Scale Plans

By Steven McFadyen on 10/29/2011 8:26 AM

If you are working on a large plan, get the real coordinates [latitude, longitude] for two or more points and add them to the drawing. That way you can always work out the scale and dimensions.

... read more..


Back to Basics - Ohm’s Law

By Steven McFadyen on 10/21/2011 2:02 PM

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 in 1827 by Georg Ohm the law defines the re... read more..


What does N+1 mean?

By Steven McFadyen on 10/19/2011 5:40 AM

The term 'N+1' relates to redundancy and simply means that if you required 'N' items of equipment for something to work, you would have one additional spare item. If any one item of equipment breaks dow... read more..


Always Use PPE

By Steven McFadyen on 10/12/2011 7:25 AM

A lot of our members work in countries where PPE (personal protective equipment) is regulated or they work for companies/organizations which take employee safety seriously. Unfortunately, there are plac... read more..


Welcome back Bottle

By Steven McFadyen on 10/9/2011 2:23 PM

‘Kept looking at a card, y’see? Kept looking at it. Welcome back Bottle. Gods below welcome home.

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Differential protection, the good old days

By Steven McFadyen on 10/3/2011 1:52 PM

This morning I was explaining how differential protection works to a junior engineer. To give him something to read I opened up the NPAG (Network Protection and Automation Guide, by Areva) and turned to... read more..




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...

Capacitor Theory

Capacitors are widely used in electrical engineering for functions such as energy storage, power factor correction, voltage compensation and many others...

Three Phase Current - Simple Calculation

The calculation of current in a three phase system has been brought up on our site feedback and is a discussion I seem to get involved in every now and...

Electromagnetic Fields - Exposure Limits

Exposure to time varying magnetic fields, from power frequencies to the gigahertz range can have harmful consequences.  A lot of research has been conducted...

IEC 60287 Current Capacity of Cables - Rated Current

In the previous note we looked at the approach taken by the standard to the sizing of cables and illustrated this with an example.  We then looked at one...

Back to basics - the Watt (or kW)

When thinking about watts (W) or kilowatt (kW = 1000 W) it can be useful too keep in mind the fundamental ideas behind the unit. Watt is not a pure electrical...

Battery Cars A to Z

Battery powered cars are a hot topic and widely debated. The pros, cons, issues and time frames can be talked about endlessly. An article by the Telegraph...

Occam's Razor

I was reminded of Occam's Razor while reading a book. It's quite a simple principal of logic which has stood the test of time and is accepted as central...

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...

IEC Reference Designations

The IEC publishes a series of documents and rules governing the preparation of documents, drawings and the referencing of equipment.   Depending on country...

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