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...

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

It starts with me reading one of the Horrible History books with my son (Groovy Greeks). Arrows were mentioned which lead to the discussion of the bodkin...

Fire resistant and fire retardant cable sheaths are design to resist combustion and limit the propagation of flames. Low smokes cables have a sheath designed...

Have an opinion or something to say, want to ask or answer questions, share your knowledge then use our site to do it . As a community of people interested...

Visitors who like to type web address rather then click menus may be interested in how our URL structure works.

Lead acid batteries are cost effect and reliable, making them suitable for many applications.This note examines topics of interest associated with the...

One of the requirements to ensuring that everything works is to have equipment selected, manufactured and verified [tested] to IEC standards. Not all equipment...

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