From the monthly archives: August 2013

We are pleased to present below all posts archived in 'August 2013'. If you still can't find what you are looking for, try using the search box.

Photovoltaic (PV) - Electrical Calculations

By Steven McFadyen on 7/11/2013 2:46 PM

Photovoltaic (PV) cells (sometimes called solar cells) convert solar energy into electrical energy.  Every year more and more PV systems are installed.  With this growing application, it's ... read more..


Fire Resistant and Fire Retardant Cables

By Steven McFadyen on 7/4/2013 1:31 PM

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 to limit the amount of smoke and toxic ha... read more..




Electromechanical Relays

Electromechanical relays have been the traditional backbone of electrical protection systems.  While over recent years these have been replaced by microprocessor...

Frame Leakage Protection

While not as popular as it once was, frame leakage protection does still have some use in some circumstances.  In essence frame leakage is an earth fault...

UPS Battery Sizing

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

Write your best report

Years ago I was told that you should always try to write the best report you can.  Many years later I still think on this as one of the better pieces of...

9 power supply issues solved by using a UPS

Installation of a UPS can help in reducing problems due to issues with the power supply.  A lot of people relate this to nine key issues.  Depending on...

How to Size Current Transformers

The correct sizing of current transformers is required to ensure satisfactory operation of measuring instruments and protection relays. Several methods...

Back to basics - the Watt (or kW)

When thinking about watts (W) or kilowatt (kW = 1000 W) it can be useful too keep in mind the fundamental ideas behind the unit. Watt is not a pure electrical...

Famous Scientists

Here’s list of some famous scientists. Deliberately short, with the aim to provide a quick memory jog or overview. If your looking for more detailed information...

The ac resistance of conductors

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...

Differential protection, the good old days

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...

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