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)...

Alternating current (a.c.) is the backbone of modern electrical power distribution. In this article I’ll be pulling some of the more important concepts...

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

How often installations are inspected is up to the owner of the installation, provided such durations do not exceed any regulatory maximums in force. ...

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

The mobile phone was born in 1973. They were the size of a brick and weighed a couple of kg, making them difficult to fit into your pocket. At a few thousand...

Often us engineers get so bogged down in equations, using software, producing drawings and writing specifications that this becomes the sole focus.   ...

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

The European Union is implementing a voluntary code of practice for participants with the aim of improving the overall efficiency of data centres. As part...

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...