Periodic Electrical Installation Inspection – How Often?
How often installations are inspected is up to the owner of the installation, provided such durations do not exceed any regulatory maximums in force. ...
DC Motor Operation
Coils of wire on the rotor carry a d.c. current which generates a magnetic field. A stator magnetic field is created using either permanent magnets or...
Paternoster Lifts
These lifts were first built in 1884 by J. E. Hall and called a paternoster ("Our Father", the first two words of the Lord's Prayer in Latin) due to its...
myElectrical - Cable Sizing Tool Upgrade
Our IEE cable sizing was wrote a few years ago and had become rough around the edges. I thought it was time to give the tool a service. Unfortunately when...
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. ...
Robotics - Home Innovations
We have a sister note to this (Robots - Interesting Video), in which I have posted some videos of interesting robots developed by commercial corporations...
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...
Magicians of Engineering
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...
E-Ink
Before the technical, some general information. E-ink display are found in a lot of e-readers, some mobile phones and similar devices and the intent is...
Generator Sizing & Operation Limits
When selecting a generator, there are inherent limits on the active and reactive power which can be delivered. Generators are normally sized for a certain...