UPS Sizing - Rules of Thumb
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...
Material Properties
Everything physical in electrical engineering from insulations to conductors revolves around materials. Here we are listing common materials along with...
What is a rectifier transformer?
I've recently come across this question a couple times browsing the internet. Decided to give a quick answer here. A rectifier transformer is a transformer...
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...
Standard Cable & Wire Sizes
IEC 60228 is the International Electrotechnical Commission's international standard on conductors of insulated cables. Among other things, it defines a...
GE's Shingijutsu Factory
GE's latest thinking on product manufacturing is he Shingijutsu philosophy or Lean production system. They have started applying this at the Louisville...
Variable Frequency Drive
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...
Cable Sizing Software
When sizing cables nearly, everyone uses some form of software. This ranges from homespun spreadsheets to complex network analyses software. Each has its...
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 to Size Current Transformers
The correct sizing of current transformers is required to ensure satisfactory operation of measuring instruments and protection relays. Several methods...