We are pleased to present below all posts archived in 'September 2011'. If you still can't find what you are looking for, try using the search box.
Motor starting and its associated problems are well-known to many people who have worked on large industrial processes. However, these things are, of course, less familiar to others. This post ... read more..
When thinking about watts (W) or kilowatt (kW = 1000 W) it can be useful too keep in mind the fundamental ideas behind the unit. Watt is not a pure electrical or mechanical unit, but is a measure of the... read more..
The (relatively new) switchgear and control gear standard, IEC 61439 'Low-voltage switchgear and controlgear assemblies' has three methods which can be...
The correct sizing of current transformers is required to ensure satisfactory operation of measuring instruments and protection relays. Several methods...
If you at all familiar with programs like office and outlook, then adding and editing posts is pretty straightforward and intuitive. However, there are...
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...
Two driverless and solar power vans have departed from Italy on their way to China via the silk road. During the 13,000 kM trip the vans will drive themselves...
A fundamental concept behind the operation of alternating current systems is that voltage and current waveforms will be sinusoidal – a Sine Wave. This...
Per unit fault calculations is a method whereby system impedances and quantities are normalised across different voltage levels to a common base. By removing...
The windings of many medium and small sized transformers are protected by restricted earth fault (REF) systems. The illustration shows the principal of...
Various arguments exist around SF6 Gas Insulated (GIS) and Air Insulated (AIS) medium voltage switchgear. Recently we had to change a GIS design to AI...
Control theory looks at how systems work and are controlled from a mathematical view. This note gives a brief introduction to some of the concepts – more...
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