A frequent problem in fault calculations is the obtaining of equipment parameters.  While it is always preferable to use the actual parameters of the equipment...

Anyone specifying or using electric motors should have a basic understanding how the insulation is related to temperature. Three classes of insulation...

The inventor of the first visible light-emitting diode makes history again this year as it begins to show customers a 40-watt replacement GE Energy Smart...

The mobile phone was born in 1973. They were the size of a brick and weighed a couple of kg, making them difficult to fit into your pocket. At a few thousand...

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...

In an earlier note on the site [Photovoltaic (PV) - Electrical Calculations], the theory of solar (PV) cell calculations was introduced.  In particular...

Photovoltaic (PV) cells (sometimes called solar cells) convert solar energy into electrical energy.  Every year more and more PV systems are installed...

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...

Electromechanical relays have been the traditional backbone of electrical protection systems.  While over recent years these have been replaced by microprocessor...

The standard aims to consolidate AC and traction voltages within the industry and defines the following bands: band 1 - A.C. systems 100 V to 1...