A UPS is an uninterruptible power supply.  It is a device which maintains a continuous supply of electrical power, even in the event of failure of 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)...

Circuit breakers are switching devices whose primary function is to isolate parts of an electrical distribution system in the even of abnormal conditions...

I'm a fan of using manufacturers catalogues. There are two main reasons for this. Firstly, if your involved in the purchase of equipment, you will likely...

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...

Our cable sizing tool is one of the more popular tools on the site.  The tool enables cables to be sized in compliance with BS 7671 (the IEE Wiring Regulations...

One of the fundamental requirements of an alternating current distribution systems it to have the ability to change the magnitude of voltages.  It is more...

While there are a vast array of cable insulation materials, these are often divided into two general types; Thermoplastic or Thermosetting. For example...

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

Maxwell's Equations are a set of fundamental relationships, which govern how electric and magnetic fields interact. The equations explain how these fields...