The other day I was reading 'Night of the New Magicians' by Mary Pope Osborn with my son.  The story is about a young boy and girl who travel back in time...

Have an opinion or something to say, want to ask or answer questions, share your knowledge then use our site to do it . As a community of people interested...

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...

IEC 62305 'Protection against lightning' requires a risk assessment be carried out to determine the characteristics of any lightning protection system...

One of the comments on my Motor Starting Series was asking for something on duty cycles. Here it is. As a purchaser of a motor, you have responsibility...

Three phase systems are derived from three separate windings, either connected in delta or star (wye). Each winding can be treated separately, leading...

From the earliest times, humans have found ways to create light. Pre-historic peoples used natural materials (moss, grass, etc.) soaked in animal fat and...

While not as popular as it once was, frame leakage protection does still have some use in some circumstances.  In essence frame leakage is an earth fault...

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...

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