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...

Often document control is dictated by project requirements, for example a particular organisation may have an existing numbering system. Existing company...

One of the comments on my Motor Starting Series was asking for something on duty cycles. Here it is. As a purchaser of a motor, you have responsibility...

Modelica is an open source (free) software language for modelling complex systems. Having never used it before, I thought I would download a development...

Depending where in the world you work, you are likely following one of two standards International Electrotechnical Commission (IEC) National...

The other day I was talking to a colleague who is a building services consultant.  Despite regularly specifying dry-type/cast resin transformers he was...

This post is quick introduction and overview to different railway electrification voltages used in answer to a question sent in via email. While there...

If your are ever called out to troubleshoot something on your electrical system, one of the first things consider is the supply voltage. You want to ensure...

Electrical notes are a collaborative collection of electrical engineering information and educational material. Any registered user can add content. ...

I was reminded of Occam's Razor while reading a book. It's quite a simple principal of logic which has stood the test of time and is accepted as central...