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...

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

There are a lot of interesting two page type notes on various medium voltage topics – switchgear, circuit breakers, bus systems etc. It is on the Siemens...

IEC 61439 'Low-voltage switchgear and controlgear assemblies', specifies standard arrangements of switchboard (call forms of internal separation). The...

Three phase systems are derived from three separate windings, either connected in delta or star (wye). Each winding can be treated separately, leading...

In a previous article I looked at the dc resistance of conductors and in this article we turn our attention to ac resistance. If you have not read the...

IEEE TV has a part series of videos on wind power and it's implication. For a really good overview to the technologies and issues around wind power, these...

This morning I was explaining how differential protection works to a junior engineer. To give him something to read I opened up the NPAG (Network Protection...

Problems on achieving maximum voltage drop within an installation come up often. Depending where you live, local regulations will have different limits...

A lot of our members work in countries where PPE (personal protective equipment) is regulated or they work for companies/organizations which take employee...