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...
Periodic Electrical Installation Inspection – What to Inspect?
This is the second post in a series of two on periodic electrical inspections. In the first post, I discussed how often inspections should be carried out...
Sony Pocket eBook Reader
For the past few years I have reading eBooks on my HTC touch phone. On and off I have debated buying an eReader and recently purchased a Sony PRS-300 ...
Switchboard - Forms of Internal Separation
IEC 61439 'Low-voltage switchgear and controlgear assemblies', specifies standard arrangements of switchboard (call forms of internal separation). The...
Meeting room of the future
The IET site has a video of a visit showing of a high tech meeting room developed at Napier University in Edinburgh. It a good demonstration of innovative...
8 Steps to Low Voltage Power Cable Selection and Sizing
A recurring theme on our forums is cable sizing. Now many installations are unique and require special consideration. However, a lot of the time things...
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...
Cable Trumps
Bored at work and would rather be playing trump card game with you son. The next best thing (or not) maybe the online cable trump card game from AEI Cables...
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...
Battery Sizing
This article gives an introduction to IEEE 485 method for the selection and calculation of battery capacity.