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 windings of many medium and small sized transformers are protected by restricted earth fault (REF) systems. The illustration shows the principal of...

The calculation of current in a three phase system has been brought up on our site feedback and is a discussion I seem to get involved in every now and...

Per unit fault calculations is a method whereby system impedances and quantities are normalised across different voltage levels to a common base.  By removing...

Visitors who like to type web address rather then click menus may be interested in how our URL structure works.

This is the second post in a series of two on periodic electrical inspections. In the first post, I discussed how often inspections should be carried out...

"I can live with doubt and uncertainty and not knowing. I think it is much more interesting to live not knowing than to have answers that might be wrong...

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...

The image (reproduced from IEC 60909) shows a typical fault in an ac system.  From the illustration it can seen that there is an initial dc component ...

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...