From the monthly archives: May 2014

We are pleased to present below all posts archived in 'May 2014'. If you still can't find what you are looking for, try using the search box.

How D.C. to A.C. Inverters Work

By Steven McFadyen on 4/22/2014 1:19 PM

Traditionally generation of electricity has involved rotating machines to produce alternating sinusoidal voltage and current (a.c. systems). With the development of power electronics during the last ... read more..




Motor Efficiency Classification

Electric motors are one of the most widely used items of electrical equipment. Improving motor efficiency benefits include, reduced power demand, lower...

Harmonised Cable Codes and Colours

Within Europe the European Committee for Electrotechnical Standardization (CENELEC) has standardised the both the designation and colour of cables.   ...

Smarter Electrical Distribution

The other day I came across an article in Technology Review on the development of a smart transformer. A professor at North Carolina State University is...

Fault Calculation - Per Unit System

Per unit fault calculations is a method whereby system impedances and quantities are normalised across different voltage levels to a common base.  By removing...

Cable Trumps

Bored at work and would rather be playing trump card game with you son. The next best thing (or not) maybe the online cable trump card game from AEI Cables...

DC Component of Asymmetrical Faults

The image (reproduced from IEC 60909) shows a typical fault in an ac system.  From the illustration it can seen that there is an initial dc component ...

Operational Amplifier

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...

Multimeter

Multimeters are undoubtedly the most common item of electrical test equipment in use.  Often it is the first piece of equipment people will turn to when...

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...

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...

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