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..




How a Digital Substation Works

Traditionally substations have used circuit breakers, current transformers (CT), voltage transformers (VT) and protection relays all wired together using...

Lighting - Lamps

Lamps are the essential part of any luminaire. These are the light generating components. Since the advent of electrical lighting in the middle of the...

What are you reading!

Reading is a bit of a hobby of mine and I"ve done a few off-topic posts in the past on this. Rather than continue doing the occasional post I thought ...

Photovoltaic (PV) Panel - Performance Modelling

In an earlier note on the site [Photovoltaic (PV) - Electrical Calculations], the theory of solar (PV) cell calculations was introduced.  In particular...

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...

How to Check a Circuit is Dead

If you want to check a circuit is dead (not live), you should always use the three point method. First check a known live circuit, then check the dead...

Maxwell's Equations - Gauss's Electric Field Law

Gauss's Electrical law defines the relation between charge ("Positive" & "Negative") and electric field.  The law was initially formulated by Carl Friedrich...

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. ...

9 power supply issues solved by using a UPS

Installation of a UPS can help in reducing problems due to issues with the power supply.  A lot of people relate this to nine key issues.  Depending on...

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...

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