From the monthly archives: October 2014

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

What is an Open Delta Transformer

By Steven McFadyen on 10/13/2014 11:54 AM

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 star, resulting in common transformer conf... read more..




Periodic Electrical Installation Inspection – What to Inspect?

This is the second post in a series of two on periodic electrical inspections. In the first post, I discussed how often inspections should be carried out...

Mobile Phones (Brick to Implant)

The mobile phone was born in 1973. They were the size of a brick and weighed a couple of kg, making them difficult to fit into your pocket. At a few thousand...

How D.C. to A.C. Inverters Work

Traditionally generation of electricity has involved rotating machines to produce alternating sinusoidal voltage and current (a.c. systems). With the development...

Variable Frequency Drive

Variable frequency drives are widely used to control the speed of ac motors.  This note looks at the mechanisms which enable drive units to control the...

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...

Resistors

Resistors are electronic components that oppose the flow of current.  Manufactured in various types and ranges they have a wide application to electronics...

Low Voltage Circuit Breakers

Circuit breakers are switching devices whose primary function is to isolate parts of an electrical distribution system in the even of abnormal conditions...

The ac resistance of conductors

In a previous article I looked at the dc resistance of conductors and in this article we turn our attention to ac resistance. If you have not read the...

Earth Electrode Resistance

Earthing of electrical systems is essential for the correct functioning and the protecting of life and equipment in the event of faults.  The earth electrode...

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...

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