From the monthly archives: July 2012

We are pleased to present below all posts archived in 'July 2012'. If you still can't find what you are looking for, try using the search box.

Fault Calculations - Typical Equipment Parameters

By Steven McFadyen on 6/24/2012 7:38 AM

A frequent problem in fault calculations is the obtaining of equipment parameters.  While it is always preferable to use the actual parameters of the equipment, sometimes these are not available... read more..


Low Voltage Fault Tables

By Steven McFadyen on 6/24/2012 7:11 AM

The following tables provide quick order of magnitude fault levels for a a range of typical low voltage situations.

read more..


Questions - Reputation and Privilege

By Steven McFadyen on 6/15/2012 9:08 AM

Our question and answer system while letting you do exactly what it says, is much more.  It is a dynamic user driven system, where our users not only ask and answer questions, but can manage the... read more..


Inductance

By Steven McFadyen on 6/3/2012 11:08 AM

When current flows within a wire, a magnetic field is created. The potion of this magnetic field perpendicular to the wire is called the magnetic flux (measured in weber, Wb). Inductance is the ratio... read more..




Motor Starting - Introduction

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...

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...

Railway Electrification Voltages

This post is quick introduction and overview to different railway electrification voltages used in answer to a question sent in via email. While there...

Welcome back Bottle

‘Kept looking at a card, y’see? Kept looking at it. Welcome back Bottle. Gods below welcome home. The Crippled God A Tale of the Malazan Book of the...

Maxwell's Equations - Introduction

Maxwell's Equations are a set of fundamental relationships, which govern how electric and magnetic fields interact. The equations explain how these fields...

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. ...

Cable Sheath and Armour Loss

When sizing cables, the heat generated  by losses within any sheath or armour need to be evaluated. When significant, it becomes a factor to be considered...

UPS Sizing - Rules of Thumb

It wasn't so long ago I was telling someone that I don't use rules of thumb as most things are easily calculated anyhow.   As it turns out I last week...

Electromagnetic Compatibility (EMC)

Electromagnetic compatibility (EMC) is the study of coordinating electromagnetic fields give off equipment, with the withstand (compatibility) of other...

Introduction to Cathodic Protection

If two dissimilar metals are touching and an external conducting path exists, corrosion of one the metals can take place.  Moisture or other materials...

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