UPS Battery Sizing
Various techniques exist to enable the correct selection of batteries for UPS applications. The procedure described below is one of the more common. ...
Software Usage Guidelines
Using software in our work is essential for most of us and we are becoming even more dependant on it's use. While software is a great asset, many times...
What is an Open Delta Transformer
In three phase systems, the use of transformers with three windings (or legs) per side is common. These three windings are often connected in delta or...
Gas Insulated or Air Insulated Switchgear
Various arguments exist around SF6 Gas Insulated (GIS) and Air Insulated (AIS) medium voltage switchgear. Recently we had to change a GIS design to AI...
Cables for MV Power Distribution - Earthed versus Unearthed Systems
Power cables can basically be classified into earthed and unearthed cables, where earthed and unearthed refer to the application for which the cable is...
Batteries
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...
How Electrical Circuits Work
If you have no idea how electrical circuits work, or what people mean then they talk about volts and amps, hopefully I can shed a bit light. I’m intending...
The ac resistance of conductors
In a previous article I looked at the dc resistance of conductors and in this article we turn our attention to ac resistance. If you have not read the...
Control Theory
Control theory looks at how systems work and are controlled from a mathematical view. This note gives a brief introduction to some of the concepts – more...
Mobile Phones (Brick to Implant)
The mobile phone was born in 1973. They were the size of a brick and weighed a couple of kg, making them difficult to fit into your pocket. At a few thousand...