The correct sizing of current transformers is required to ensure satisfactory operation of measuring instruments and protection relays. Several methods...

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...

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...

We have had the Wiki with us for a long time now, but at last I have decided to say bye bye – more details on why below.

When thinking about watts (W) or kilowatt (kW = 1000 W) it can be useful too keep in mind the fundamental ideas behind the unit. Watt is not a pure electrical...

Problems on achieving maximum voltage drop within an installation come up often. Depending where you live, local regulations will have different limits...

A lot of our members work in countries where PPE (personal protective equipment) is regulated or they work for companies/organizations which take employee...

Induction motors are frequently used in both industrial and domestic applications.  Within the induction motor, an electrical current in the rotor is induced...

Request to look at induction motor starting time have come up a few times on the site. Hopefully in this post, I give you guys some idea on how to calculate...

In three phase systems, the use of transformers with three windings (or legs) per side is common.  These three windings are often connected in delta or...