Electromechanical relays have been the traditional backbone of electrical protection systems.  While over recent years these have been replaced by microprocessor...

Nikola Tesla was born exactly at midnight on July 10, 1856 in the tiny village of Smiljan, Lika in Croatia. In his late teens, Tesla left the village to...

For unbalance conditions the calculation of fault currents is more complex. One method of dealing with this is symmetrical components. Using symmetrical...

Low voltage (LV) switchrooms are common across all industries and one of the more common spatial requirements which need to be designed into a project...

When sizing cables nearly, everyone uses some form of software. This ranges from homespun spreadsheets to complex network analyses software. Each has its...

MIT OpenCourseWare, makes the materials used in teaching all MIT subjects available on the Web, free of charge, to any user in the world.

Ever wondered what kind of power an aircraft uses when parked at the airport stand. Normally the aircraft generates it own power, but when parked with...

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 image (reproduced from IEC 60909) shows a typical fault in an ac system.  From the illustration it can seen that there is an initial dc component ...

Some colleagues had an issue earlier in the week on sizing conduits to be cast in concrete for some power cables . It became clear that none of us had...