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...

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...

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...

A load flow study is the analysis of an electrical network carried out by an electrical engineer. The purpose is to understand how power flows around...

Traditionally substations have used circuit breakers, current transformers (CT), voltage transformers (VT) and protection relays all wired together using...

If two dissimilar metals are touching and an external conducting path exists, corrosion of one the metals can take place.  Moisture or other materials...

The (relatively new) switchgear and control gear standard, IEC 61439 'Low-voltage switchgear and controlgear assemblies' has three methods which can be...

Steel ladders, trays and baskets form the backbone of cable containment systems. Often these items need some form of surface treatment to prevent corrosion...

The new standard IEC 61439 replaces the old 60439. Compared to the old standard, the new 61439 is a more clearly defined and takes into account the assembly...

IEC 60287 "Calculation of the continuous current rating of cables (100% load factor)" is the International Standard which defines the procedures and equations...