RLC Circuit, Resistor Power Loss - some Modelica experiments

By Steven McFadyen on 1/20/2014 1:32 PM

Modelica is an open source (free) software language for modelling complex systems. Having never used it before, I thought I would download a development platform and see how it stacked up.  This... read more..


Lead Acid Batteries

By Steven McFadyen on 3/3/2012 12:57 PM

Lead acid batteries are cost effect and reliable, making them suitable for many applications.This note examines topics of interest associated with the use of these batteriesLead acid batteries are co... read more..


Capacitors - Energy Storage Application

By Steven McFadyen on 6/29/2013 8:24 PM

Capacitors have numerous applications in electrical and electronic applications.  This note examines the use of capacitors to store electrical energy.  The sidebar shows details of a typical c... read more..


Calculating Cable Fault Ratings

By Steven McFadyen on 1/6/2014 1:22 PM

When selecting a cable, the performance of the cable under fault conditions is an important consideration. It is important that calculations be carried out to ensure that any cable is able to withstand ... read more..


Our internet address and Vanity URLs

By Steven McFadyen on 6/2/2011 5:03 AM

Visitors who like to type web address rather then click menus may be interested in how our URL structure works... read more..


Variable Frequency Drive

By Steven McFadyen on 3/28/2012 9:58 PM

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


IEC 60287 Current Capacity of Cables - Rated Current

By Steven McFadyen on 2/18/2013 5:58 AM

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 method of applying the standard and iden... read more..


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..


Earth Electrode Resistance

By Steven McFadyen on 5/17/2012 11:37 AM

Earthing of electrical systems is essential for the correct functioning and the protecting of life and equipment in the event of faults.  The earth electrode (connection of the earthing system t... read more..


Post Authorship

By Steven McFadyen on 4/15/2012 1:53 PM

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


Operational Amplifier

By Steven McFadyen on 5/17/2012 12:47 PM

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-gain electronic voltage amplifier with a diffe... read more..


Post Editing Tips

By Steven McFadyen on 5/28/2012 2:08 PM

If you at all familiar with programs like office and outlook, then adding and editing posts is pretty straightforward and intuitive.  However, there are a few things which which can life a easier t... read more..




Low Voltage Fault Tables

The following tables provide quick order of magnitude fault levels for a a range of typical low voltage situations.

Switchboard - Forms of Internal Separation

IEC 61439 'Low-voltage switchgear and controlgear assemblies', specifies standard arrangements of switchboard (call forms of internal separation). The...

Difference Between Live and Dead Tank Circuit Breakers

A quick post in connection with an email question: Live Tank - the circuit breaker the switching unit is located in an insulator bushing which is live...

Low Voltage Switchroom Design Guide

Low voltage (LV) switchrooms are common across all industries and one of the more common spatial requirements which need to be designed into a project...

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. ...

Fault Calculation - Symmetrical Components

For unbalance conditions the calculation of fault currents is more complex. One method of dealing with this is symmetrical components. Using symmetrical...

Restricted Earth Fault Protection

The windings of many medium and small sized transformers are protected by restricted earth fault (REF) systems. The illustration shows the principal of...

Windows Live Writer and myElectrical

When making adding a Note to our site we have a great online WYSIWYG editor and things are pretty simple.  However, if you prefer you can write, manage...

Electrical Engineering

Electrical engineering is a field that covers a wide variety of sub-fields, including electricity and electronics. It is a field that goes back to the...

Why use catalogues

I'm a fan of using manufacturers catalogues. There are two main reasons for this. Firstly, if your involved in the purchase of equipment, you will likely...

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