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..




The ac resistance of conductors

In a previous article I looked at the dc resistance of conductors and in this article we turn our attention to ac resistance. If you have not read the...

Microsoft OneNote

A couple of months ago I came Microsoft's OneNote and downloaded the 60 day free trail. Since then I have been using it regularly and now have a full license...

How Electrical Circuits Work

If you have no idea how electrical circuits work, or what people mean then they talk about volts and amps, hopefully I can shed a bit light.  I’m intending...

Equipment Verification (to IEC Standards)

One of the requirements to ensuring that everything works is to have equipment selected, manufactured and verified [tested] to IEC standards. Not all equipment...

Star-Delta Motor Starting - Performance

Many questions sent in to the site are in connection with motor starting and in particular star-delta.  For all but the simplest application, there is...

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...

Induction Motor Calculator

Just added a page to the tools, which will allow you to calculate the synchronous speed, slip and rated torque for an induction motor. Not a particularly...

Voltage Drop in Installations - Concepts

Problems on achieving maximum voltage drop within an installation come up often. Depending where you live, local regulations will have different limits...

Power Transformers - An Introduction

One of the fundamental requirements of an alternating current distribution systems it to have the ability to change the magnitude of voltages.  It is more...

IEC Document Designation

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

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