Various techniques exist to enable the correct selection of batteries for UPS applications.  The procedure described below is one of the more common. ...

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The International System of Units (abbreviated SI) is the world's most widely used system of units.  The system consists of a set of units and prefixes...

It starts with me reading one of the Horrible History books with my son (Groovy Greeks). Arrows were mentioned which lead to the discussion of the bodkin...

Exposure to time varying magnetic fields, from power frequencies to the gigahertz range can have harmful consequences.  A lot of research has been conducted...

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...

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...

For unbalance conditions the calculation of fault currents is more complex. One method of dealing with this is symmetrical components. Using symmetrical...

I was digging in my bookshelf and came across the 80th Anniversary Association of Mine Resident Engineers, Papers and Discussions Commemorative Edition...

Three phase systems are derived from three separate windings, either connected in delta or star (wye). Each winding can be treated separately, leading...