Battery Sizing
This article gives an introduction to IEEE 485 method for the selection and calculation of battery capacity.
RLC Circuit, Resistor Power Loss - some Modelica experiments
Modelica is an open source (free) software language for modelling complex systems. Having never used it before, I thought I would download a development...
Tip – Latitude and Longitude on Large Scale Plans
If you are working on a large plan, get the real coordinates [latitude, longitude] for two or more points and add them to the drawing. That way you can...
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...
Why is electricity so hard to understand?
It's been a busy few months on different projects or busy couple of decades depending on how I look at it. I can say that on the odd (frequent) occasion...
Power Factor
Power factor is the ratio between the real power (P in kW) and apparent power (S in kVA) drawn by an electrical load. The reactive power (Q in kVAr)...
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...
Star-Delta Motor Starting - Performance
Many questions sent in to the site are in connection with motor starting and in particular star-delta. For all but the simplest application, there is...
Our internet address and Vanity URLs
Visitors who like to type web address rather then click menus may be interested in how our URL structure works.
LED Replacement Light Bulb
The inventor of the first visible light-emitting diode makes history again this year as it begins to show customers a 40-watt replacement GE Energy Smart...