From the monthly archives: August 2009

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

IEC 61439 - The Switchgear Standard

By Steven McFadyen on 7/1/2009 3:08 AM

The new standard IEC 61439 replaces the old 60439. Compared to the old standard, the new 61439 is a more clearly defined and takes into account the assembly of pre-tested designs. .

Some key... read more..




Tech Topics/Application Notes - Siemens

There are a lot of interesting two page type notes on various medium voltage topics – switchgear, circuit breakers, bus systems etc. It is on the Siemens...

Power Factor

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)...

Motor Insulation

Insulation on a motor prevents interconnection of windings and the winding to earth.  When looking at motors, it is important to understand how the insulation...

HTML Symbol Entities

HTML supports a variety of entity symbols which can be entered using either numbers or an entity name.  The number or name is preceded by the ‘&’ sign...

New Mail Chimp

We've been sending out Newsletters on a regular basis for a few weeks now. To do this we have been using Google's Feedburner service. While Feedburner...

Network Theory – Introduction and Review

In electrical engineering, Network Theory is the study of how to solve circuit problems. By analyzing circuits, the engineer looks to determine the various...

Autonomous Vehicle Challenge

Two driverless and solar power vans have departed from Italy on their way to China via the silk road. During the 13,000 kM trip the vans will drive themselves...

What is an Open Delta Transformer

In three phase systems, the use of transformers with three windings (or legs) per side is common.  These three windings are often connected in delta or...

8 Steps to Low Voltage Power Cable Selection and Sizing

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...

What is a rectifier transformer?

I've recently come across this question a couple times browsing the internet. Decided to give a quick answer here. A rectifier transformer is a transformer...

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