From the monthly archives: August 2014

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

Star-Delta Motor Starting - Performance

By Steven McFadyen on 7/10/2014 3:51 PM

Many questions sent in to the site are in connection with motor starting and in particular star-delta.  For all but the simplest application, there is merit in performing a more detailed study.&... read more..




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...

Introduction to Traction Substations

Following on from my post on railway electrification voltages, I thought an introduction to traction substations would be a good idea. Traction substations...

Why a Sine Wave?

I received this question by email a few weeks. First thoughts was that it is a product of the mathematics of rotating a straight conductor in a magnetic...

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)...

Post Authorship

In 2011, with the introduction of it’s Panda search ranking algorithms, Google introduced tools for determining the original author of posts.  The intention...

Lightning Protection and Earth Electrode Resistance

Most installations involve some form of lightning protection system which is connected to an earth electrode.  The function of the earth electrode is to...

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...

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...

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...

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. ...

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