UPS Battery Sizing


Various techniques exist to enable the correct selection of batteries for UPS applications.  The procedure described below is one of the more common. It is also possible to use the IEEE 485 method (see link at the bottom of the page)....Read More..

By Steven McFadyen on Sunday, April 08, 2012

Photovoltaic (PV) - Electrical Calculations


Photovoltaic (PV) cells (sometimes called solar cells) convert solar energy into electrical energy.  Every year more and more PV systems are installed.  With this growing application, it's a good idea for every practicing professional to have an understanding of the calculations associated with PV cells....Read More..

By Steven McFadyen on Thursday, July 11, 2013

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 previous article, now may be a good time to do so. The ac resistance of a conductor is always larger than the dc resistance. The primary reasons for this are 'skin effect......Read More..

By Steven McFadyen on Wednesday, January 11, 2012

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