From the monthly archives: April 2014

We are pleased to present below all posts archived in 'April 2014'. If you still can't find what you are looking for, try using the search box.

How a Digital Substation Works

By Steven McFadyen on 3/2/2014 12:06 PM

Traditionally substations have used circuit breakers, current transformers (CT), voltage transformers (VT) and protection relays all wired together using copper cables.  With advances in digital... read more..




Gas Insulated or Air Insulated Switchgear

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...

Fire Resistant and Fire Retardant Cables

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...

The dc resistance of conductors

This is the first of two posts on the resistance of conductors. In the next post I will look at the ac resistance, including skin effect and we deal with...

Load Flow Study – how they work

A load flow study is the analysis of an electrical network carried out by an electrical engineer. The purpose is to understand how power flows around...

What does N+1 mean?

The term 'N+1' relates to redundancy and simply means that if you required 'N' items of equipment for something to work, you would have one additional...

Periodic Electrical Installation Inspection – How Often?

How often installations are inspected is up to the owner of the installation, provided such durations do not exceed any regulatory maximums in force. ...

How to Check a Circuit is Dead

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...

Cable Sizing Tool

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...

Dielectric loss in cables

Dielectrics (insulating materials for example) when subjected to a varying electric field, will have some energy loss.   The varying electric field causes...

How to Write an Electrical Note

Electrical notes are a collaborative collection of electrical engineering information and educational material. Any registered user can add content. ...

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