From the monthly archives: November 2009

We are pleased to present below all posts archived in 'November 2009'. If you still can't find what you are looking for, try using the search box.

Lightning Protection and Earth Electrode Resistance

By Steven McFadyen on 11/22/2009 7:48 PM

Most installations involve some form of lightning protection system which is connected to an earth electrode.  The function of the earth electrode is to dissipate the lightning strike safely in to ... read more..


1,000 kV UHV First for China

By Steven McFadyen on 11/3/2009 8:33 PM

At the beginning of the year China put the world's first 1,000 kV UHV transmission system into operation. Transmitting power at over a million volts is just amazing.  Some key facts about the syste... read more..




Medium Voltage Switchgear Room Design Guide

Many medium voltage (MV) indoor switchgear rooms  exist worldwide. The complexity of these rooms varies considerably depending on location, function and...

Hazardous Areas – IEC and NEC/CEC Comparison

Depending where in the world you work, you are likely following one of two standards International Electrotechnical Commission (IEC) National...

Fault Calculation - Per Unit System

Per unit fault calculations is a method whereby system impedances and quantities are normalised across different voltage levels to a common base.  By removing...

How to refer fault levels across a transformer

Over the past year or so I've been involved in on going discussions related to referring fault levels from the secondary of a transformer to the primary...

Understanding Circuit Breaker Markings

IEC 60947 is the circuit breaker standard and covers the marking of breakers in detail. Any manufacturer following this standard should comply with the...

Closed Doors

"I can live with doubt and uncertainty and not knowing. I think it is much more interesting to live not knowing than to have answers that might be wrong...

Always Use PPE

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

Voltage Levels – Confused?

I was having a conversation the other day about voltage levels.  While everyone was in agreement that low voltage was 1000 V and less, there was more confusion...

Switchboard - Forms of Internal Separation

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

Meeting room of the future

The IET site has a video of a visit showing of a high tech meeting room developed at Napier University in Edinburgh. It a good demonstration of innovative...

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