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)...

Various arguments exist around SF6 Gas Insulated (GIS) and Air Insulated (AIS) medium voltage switchgear. Recently we had to change a GIS design to AI...

This post is quick introduction and overview to different railway electrification voltages used in answer to a question sent in via email. While there...

When selecting a generator, there are inherent limits on the active and reactive power which can be delivered. Generators are normally sized for a certain...

A single phase system is perhaps the most common type of system most people are familiar with. This is what people have in their homes and what appliances...

I was reminded of Occam's Razor while reading a book. It's quite a simple principal of logic which has stood the test of time and is accepted as central...

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...

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

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...

A recurring theme on our forums is cable sizing. Now many installations are unique and require special consideration. However, a lot of the time things...