Lead acid batteries are cost effect and reliable, making them suitable for many applications.This note examines topics of interest associated with the...

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

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

Coils of wire on the rotor carry a d.c. current which generates a magnetic field. A stator magnetic field is created using either permanent magnets or...

It starts with me reading one of the Horrible History books with my son (Groovy Greeks). Arrows were mentioned which lead to the discussion of the bodkin...

If your are ever called out to troubleshoot something on your electrical system, one of the first things consider is the supply voltage. You want to ensure...

It wasn't so long ago I was telling someone that I don't use rules of thumb as most things are easily calculated anyhow.   As it turns out I last week...

At the beginning of the year China put the world's first 1,000 kV UHV transmission system into operation. Transmitting power at over a million volts is...

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

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...