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 ...

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...

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...

In three phase systems, the use of transformers with three windings (or legs) per side is common.  These three windings are often connected in delta or...

Modelica is an open source (free) software language for modelling complex systems. Having never used it before, I thought I would download a development...

Low voltage (LV) switchrooms are common across all industries and one of the more common spatial requirements which need to be designed into a project...

In 2011, with the introduction of it’s Panda search ranking algorithms, Google introduced tools for determining the original author of posts.  The intention...

It's been a busy few months on different projects or busy couple of decades depending on how I look at it. I can say that on the odd (frequent) occasion...

Over the past year or so I've been involved in on going discussions related to referring fault levels from the secondary of a transformer to the primary...

Depending where in the world you work, you are likely following one of two standards International Electrotechnical Commission (IEC) National...