From the monthly archives: September 2011

We are pleased to present below all posts archived in 'September 2011'. If you still can't find what you are looking for, try using the search box.

Motor Starting - Introduction

By Steven McFadyen on 8/11/2011 1:28 AM

Motor starting and its associated problems are well-known to many people who have worked on large industrial processes. However, these things are, of course, less familiar to others.  This post ... read more..


Back to basics - the Watt (or kW)

By Steven McFadyen on 8/4/2011 1:13 AM

When thinking about watts (W) or kilowatt (kW = 1000 W) it can be useful too keep in mind the fundamental ideas behind the unit. Watt is not a pure electrical or mechanical unit, but is a measure of the... read more..




Laplace Transform

Laplace transforms and their inverse are a mathematical technique which allows us to solve differential equations, by primarily using algebraic methods...

How to Size Current Transformers

The correct sizing of current transformers is required to ensure satisfactory operation of measuring instruments and protection relays. Several methods...

Maxwell's Equations - Gauss's Electric Field Law

Gauss's Electrical law defines the relation between charge ("Positive" & "Negative") and electric field.  The law was initially formulated by Carl Friedrich...

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...

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...

Photovoltaic (PV) - Electrical Calculations

Photovoltaic (PV) cells (sometimes called solar cells) convert solar energy into electrical energy.  Every year more and more PV systems are installed...

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...

Understanding LV Circuit Breaker Fault Ratings

I think this post is going to be helpful to several of our readers. While the IEC low voltage circuit breaker Standard [IEC 60947-2, Low voltage switchgear...

How to Size Power Cable Duct

Some colleagues had an issue earlier in the week on sizing conduits to be cast in concrete for some power cables . It became clear that none of us had...

3 Phase Loads

Three phase systems are derived from three separate windings, either connected in delta or star (wye). Each winding can be treated separately, leading...

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