Frame Leakage Protection
While not as popular as it once was, frame leakage protection does still have some use in some circumstances. In essence frame leakage is an earth fault...
What happened to the cable notes?
If you are wondering what happened to our cable notes, the short answer is that we have moved them to myCableEngineering.com. The "Knowledge Base" at...
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...
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...
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...
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...
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...
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...
110 or 230 Volts
I've been considering a blog on the 110 or 230 Volt issue for a while. While browsing the Internet I came across a great summary by Borat over at engineering...
Understanding electric motor insulation & temperature
Anyone specifying or using electric motors should have a basic understanding how the insulation is related to temperature. Three classes of insulation...