From the monthly archives: September 2009

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

Closed Doors

By Steven McFadyen on 8/28/2009 1:03 AM

"I can live with doubt and uncertainty and not knowing. I think it is much more interesting to live not knowing than to have answers that might be wrong. If we will only allow that, as we progress, we r... read more..


IEC Reference Designations

By Steven McFadyen on 8/26/2009 11:55 PM

The IEC publishes a series of documents and rules governing the preparation of documents, drawings and the referencing of equipment.   Depending on country and industry, people are either f... read more..


Gas Insulated or Air Insulated Switchgear

By Steven McFadyen on 8/11/2009 2:32 AM

Various arguments exist around SF6 Gas Insulated (GIS) and Air Insulated (AIS) medium voltage switchgear. Recently we had to change a GIS design to AIS due to an instruction from&nbs... read more..


110 or 230 Volts

By Steven McFadyen on 8/2/2009 10:50 PM

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.com.  He ... read more..


Occam's Razor

By Steven McFadyen on 8/2/2009 4:11 AM

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 to scientific thought. Without thi... read more..




Tips for a better Low Voltage Protection Discrimination Study

Carrying out a protection system discrimination study is critical to ensure the correct functioning of  the electrical system in the event of faults. ...

Differential protection, the good old days

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...

RLC Circuit, Resistor Power Loss - some Modelica experiments

Modelica is an open source (free) software language for modelling complex systems. Having never used it before, I thought I would download a development...

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...

Copyright Infringement

myElectrical does not support or promote the use of copyrighted material without the copyright owner's consent. If you believe that material for which...

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...

Photovoltaic (PV) - Utility Power Grid Interface

Photovoltaic (PV) systems are typically more efficient when connected in parallel with a main power gird. During periods when the PV system generates energy...

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...

Motor Insulation

Insulation on a motor prevents interconnection of windings and the winding to earth.  When looking at motors, it is important to understand how the insulation...

Useful Motor Technical Information

Sometimes it’s useful to be able to quickly lookup a piece of technical information.  This note is a collection of information related to motors, and in...

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