From the monthly archives: December 2011

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

Understanding LV Circuit Breaker Fault Ratings

By Steven McFadyen on 12/18/2011 12:20 PM

I think this post is going to be helpful to several of our readers. While the IEC low voltage circuit breaker Standard [IEC 60947-2, Low voltage switchgear and controlgear - Part 2: Circuit-breakers] ha... read more..


Understanding Motor Duty Rating

By Steven McFadyen on 12/12/2011 8:05 AM

One of the comments on my Motor Starting Series was asking for something on duty cycles. Here it is.

As a... read more..


8 Motor parts and common faults

By Steven McFadyen on 12/6/2011 6:07 AM

Straight forward list of some common motor faults.  If I have missed any other common faults, please take a bit of time to add them in as a comment below. read more..


myElectrical - Cable Sizing Tool Upgrade

By Steven McFadyen on 12/2/2011 4:56 AM

Our IEE cable sizing was wrote a few years ago and had become rough around the edges. I thought it was time to give the tool a service. Unfortunately when I looked under the hood I found cracked cylinde... read more..




Operational Amplifier

The fundamental component of any analogue computer is the operational amplifier, or op amp. An operational amplifier (often called an op-amp,) is a high...

ABB Technical Guides - Motor Operation

ABB has produced a range of technical guides that offer concise explanations of the major technologies and technical issues in low voltage AC drives. ...

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...

Variable Frequency Drive

Variable frequency drives are widely used to control the speed of ac motors.  This note looks at the mechanisms which enable drive units to control the...

Load Flow Study – how they work

A load flow study is the analysis of an electrical network carried out by an electrical engineer. The purpose is to understand how power flows around...

Post Authorship

In 2011, with the introduction of it’s Panda search ranking algorithms, Google introduced tools for determining the original author of posts.  The intention...

Motor Starting - Introduction

Motor starting and its associated problems are well-known to many people who have worked on large industrial processes. However, these things are, of course...

Resistors

Resistors are electronic components that oppose the flow of current.  Manufactured in various types and ranges they have a wide application to electronics...

IEC Document Designation

Often document control is dictated by project requirements, for example a particular organisation may have an existing numbering system. Existing company...

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...

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