Exposure to time varying magnetic fields, from power frequencies to the gigahertz range can have harmful consequences.  A lot of research has been conducted...

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...

A single phase system is perhaps the most common type of system most people are familiar with. This is what people have in their homes and what appliances...

Motor starting and its associated problems are well-known to many people who have worked on large industrial processes. However, these things are, of course...

HTML supports a variety of entity symbols which can be entered using either numbers or an entity name.  The number or name is preceded by the ‘&’ sign...

Maxwell's Equations are a set of fundamental relationships, which govern how electric and magnetic fields interact. The equations explain how these fields...

This is the second post in a series of two on periodic electrical inspections. In the first post, I discussed how often inspections should be carried out...

There are a lot of interesting two page type notes on various medium voltage topics – switchgear, circuit breakers, bus systems etc. It is on the Siemens...

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...

Sometimes it’s useful to be able to quickly lookup a piece of technical information.  This note is a collection of information related to motors, and in...