Fault calculations are one of the most common types of calculation carried out during the design and analysis of electrical systems. These calculations...

Per unit fault calculations is a method whereby system impedances and quantities are normalised across different voltage levels to a common base.  By removing...

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)...

The fundamental component of any analogue computer is the operational amplifier, or op amp. An operational amplifier (often called an op-amp,) is a high...

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...

The following tables provide quick order of magnitude fault levels for a a range of typical low voltage situations.

Just added a page to the tools, which will allow you to calculate the synchronous speed, slip and rated torque for an induction motor. Not a particularly...

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...

Two driverless and solar power vans have departed from Italy on their way to China via the silk road. During the 13,000 kM trip the vans will drive themselves...

Most installations involve some form of lightning protection system which is connected to an earth electrode.  The function of the earth electrode is to...