When selecting a cable, the performance of the cable under fault conditions is an important consideration. It is important that calculations be carried...

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...

HTML supports a variety of entity symbols which can be entered using either numbers or an entity name.  The number or name is preceded by the ‘&’ sign...

These lifts were first built in 1884 by J. E. Hall and called a paternoster ("Our Father", the first two words of the Lord's Prayer in Latin) due to its...

Various techniques exist to enable the correct selection of batteries for UPS applications.  The procedure described below is one of the more common. ...

If you want to check a circuit is dead (not live), you should always use the three point method. First check a known live circuit, then check the dead...

If you have no idea how electrical circuits work, or what people mean then they talk about volts and amps, hopefully I can shed a bit light.  I’m intending...

The windings of many medium and small sized transformers are protected by restricted earth fault (REF) systems. The illustration shows the principal of...

Coils of wire on the rotor carry a d.c. current which generates a magnetic field. A stator magnetic field is created using either permanent magnets or...

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...