From the monthly archives: February 2012

We are pleased to present below all posts archived in 'February 2012'. If you still can't find what you are looking for, try using the search box.

Introduction to Traction Substations

By Steven McFadyen on 2/26/2012 12:16 PM

Following on from my post on railway electrification voltages, I thought an introduction to traction substation... read more..


How to measure power supply quality

By Steven McFadyen on 2/14/2012 11:43 AM

If your are ever called out to troubleshoot something on your electrical system, one of the first things consider is the supply voltage. You want to ensure you have a good electrical supply before movin... read more..


Why use catalogues

By Steven McFadyen on 2/8/2012 5:35 AM

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 need to look into catalogues to find what you ne... read more..


Induction Motor Calculator

By Steven McFadyen on 2/2/2012 1:15 PM

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 complicated calculation, but anything the mak... read more..




How to Write an Electrical Note

Electrical notes are a collaborative collection of electrical engineering information and educational material. Any registered user can add content. ...

Cables for MV Power Distribution - Earthed versus Unearthed Systems

Power cables can basically be classified into earthed and unearthed cables, where earthed and unearthed refer to the application for which the cable is...

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...

What does N+1 mean?

The term 'N+1' relates to redundancy and simply means that if you required 'N' items of equipment for something to work, you would have one additional...

Famous Scientists

Here’s list of some famous scientists. Deliberately short, with the aim to provide a quick memory jog or overview. If your looking for more detailed information...

Paternoster Lifts

These lifts were first built in 1884 by J. E. Hall and called a paternoster ("Our Father", the first two words of the Lord's Prayer in Latin) due to its...

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...

Cable Sizing Tool

Our cable sizing tool is one of the more popular tools on the site.  The tool enables cables to be sized in compliance with BS 7671 (the IEE Wiring Regulations...

IEC Reference Designations

The IEC publishes a series of documents and rules governing the preparation of documents, drawings and the referencing of equipment.   Depending on country...

What is LED?

Light Emitting Diodes (LED ) are increasing gaining favour in both the domestic and commercial sectors; due to their efficiency, sustainability and durability...

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