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..




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...

Gas Insulated or Air Insulated Switchgear

Various arguments exist around SF6 Gas Insulated (GIS) and Air Insulated (AIS) medium voltage switchgear. Recently we had to change a GIS design to AI...

Network Theory – Introduction and Review

In electrical engineering, Network Theory is the study of how to solve circuit problems. By analyzing circuits, the engineer looks to determine the various...

Cable Sheath and Armour Loss

When sizing cables, the heat generated  by losses within any sheath or armour need to be evaluated. When significant, it becomes a factor to be considered...

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. ...

Aluminium Windings - Dry Type Transformers

The other day I was talking to a colleague who is a building services consultant.  Despite regularly specifying dry-type/cast resin transformers he was...

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...

Cost Performance and Time

Often us engineers get so bogged down in equations, using software, producing drawings and writing specifications that this becomes the sole focus.   ...

UPS - Uninterruptible Power Supply

A UPS is an uninterruptible power supply.  It is a device which maintains a continuous supply of electrical power, even in the event of failure of the...

What is a rectifier transformer?

I've recently come across this question a couple times browsing the internet. Decided to give a quick answer here. A rectifier transformer is a transformer...

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