This article gives an introduction to IEEE 485 method for the selection and calculation of battery capacity.

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

The other day I was talking to a colleague who is a building services consultant.  Despite regularly specifying dry-type/cast resin transformers he was...

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...

We have had the Wiki with us for a long time now, but at last I have decided to say bye bye – more details on why below.

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...

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...

A battery consists of one or more cells, each of which use stored chemical energy to produce electrical energy, There are many types of cells and these...

"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...

Following on from my post on railway electrification voltages, I thought an introduction to traction substations would be a good idea. Traction substations...