From the monthly archives: January 2015

We are pleased to present below all posts archived in 'January 2015'. If you still can't find what you are looking for, try using the search box.

Photovoltaic (PV) Panel - Performance Modelling

By Steven McFadyen on 1/8/2015 3:55 AM

In an earlier note on the site [Photovoltaic (PV) - Electrical Calculations], the theory of solar (PV) ... read more..




myElectrical - Cable Sizing Tool Upgrade

Our IEE cable sizing was wrote a few years ago and had become rough around the edges. I thought it was time to give the tool a service. Unfortunately when...

8 Motor parts and common faults

Straight forward list of some common motor faults.  If I have missed any other common faults, please take a bit of time to add them in as a comment below...

Star-Delta Motor Starting - Performance

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...

Fault Calculation - Per Unit System

Per unit fault calculations is a method whereby system impedances and quantities are normalised across different voltage levels to a common base.  By removing...

Back to Basics - Ohm’s Law

Electrical engineering has a multitude of laws and theorems. It is fair to say the Ohm's Law is one of the more widely known; it not the most known. Developed...

Photovoltaic (PV) - Utility Power Grid Interface

Photovoltaic (PV) systems are typically more efficient when connected in parallel with a main power gird. During periods when the PV system generates energy...

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...

Paths of Flight

GE have put together a time-lapse video shown flight take-off and landings at some airports. An interesting view:

Electromechanical Relays

Electromechanical relays have been the traditional backbone of electrical protection systems.  While over recent years these have been replaced by microprocessor...

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...

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