The correct sizing of current transformers is required to ensure satisfactory operation of measuring instruments and protection relays. Several methods...

Variable frequency drives are widely used to control the speed of ac motors.  This note looks at the mechanisms which enable drive units to control the...

The following tables provide quick order of magnitude fault levels for a a range of typical low voltage situations.

How often installations are inspected is up to the owner of the installation, provided such durations do not exceed any regulatory maximums in force. ...

GE have put together a time-lapse video shown flight take-off and landings at some airports. An interesting view:

When selecting a cable, the performance of the cable under fault conditions is an important consideration. It is important that calculations be carried...

When making adding a Note to our site we have a great online WYSIWYG editor and things are pretty simple.  However, if you prefer you can write, manage...

There are a lot of interesting two page type notes on various medium voltage topics – switchgear, circuit breakers, bus systems etc. It is on the Siemens...

The other day I was reading 'Night of the New Magicians' by Mary Pope Osborn with my son.  The story is about a young boy and girl who travel back in time...

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  While over recent years these have been replaced by microprocessor...