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.

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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..




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...

Induction Motor Equivalent Circuit

Induction motors are frequently used in both industrial and domestic applications.  Within the induction motor, an electrical current in the rotor is induced...

Voltage Levels – Confused?

I was having a conversation the other day about voltage levels.  While everyone was in agreement that low voltage was 1000 V and less, there was more confusion...

Frame Leakage Protection

While not as popular as it once was, frame leakage protection does still have some use in some circumstances.  In essence frame leakage is an earth fault...

Medium Voltage Switchgear Room Design Guide

Many medium voltage (MV) indoor switchgear rooms  exist worldwide. The complexity of these rooms varies considerably depending on location, function and...

IEC 61439 Verification Methods

The (relatively new) switchgear and control gear standard, IEC 61439 'Low-voltage switchgear and controlgear assemblies' has three methods which can be...

Getting Started with Patents

If you have a great idea or invent something the last thing you want is someone to steal the idea. One of the things you can do is protect the intellectual...

Large Hadron Collider

The 27 km, Euro 6 billion  Collider lies on the border between France and Switzerland, took nearly 30 years to complete.  Some of the lofty goals for the...

Power Transformers - An Introduction

One of the fundamental requirements of an alternating current distribution systems it to have the ability to change the magnitude of voltages.  It is more...

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...

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