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...
Nikola Tesla
Nikola Tesla was born exactly at midnight on July 10, 1856 in the tiny village of Smiljan, Lika in Croatia. In his late teens, Tesla left the village to...
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...
Differential protection, the good old days
This morning I was explaining how differential protection works to a junior engineer. To give him something to read I opened up the NPAG (Network Protection...
Electromagnetic Fields - Exposure Limits
Exposure to time varying magnetic fields, from power frequencies to the gigahertz range can have harmful consequences. A lot of research has been conducted...
Capacitor Theory
Capacitors are widely used in electrical engineering for functions such as energy storage, power factor correction, voltage compensation and many others...
ANSI (IEEE) Protective Device Numbering
The widely used United Sates standard ANSI/IEEE C37.2 'Electrical Power System Device Function Numbers, Acronyms, and Contact Designations' deals with...
Introduction to Lighting
When looking at the design of a lighting scheme it is useful to have an understanding on the nature of light itself and some of the basic theory associated...
Maximum Demand for Buildings
Estimating maximum demand is a topic frequently discussed. Working out how much power to allow for a building can be very subjective . Allowing too much...
Post Editing Tips
If you at all familiar with programs like office and outlook, then adding and editing posts is pretty straightforward and intuitive. However, there are...