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

HTML supports a variety of entity symbols which can be entered using either numbers or an entity name.  The number or name is preceded by the ‘&’ sign...

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

If you are working on a large plan, get the real coordinates [latitude, longitude] for two or more points and add them to the drawing. That way you can...

Problems on achieving maximum voltage drop within an installation come up often. Depending where you live, local regulations will have different limits...

Power factor is the ratio between the real power (P in kW) and apparent power (S in kVA) drawn by an electrical load. The reactive power (Q in kVAr)...

Reading is a bit of a hobby of mine and I"ve done a few off-topic posts in the past on this. Rather than continue doing the occasional post I thought ...

Straight forward list of some common motor faults.  If I have missed any other common faults, please take a bit of time to add them in as a comment below...

Most installations involve some form of lightning protection system which is connected to an earth electrode.  The function of the earth electrode is to...

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...