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..




How to refer fault levels across a transformer

Over the past year or so I've been involved in on going discussions related to referring fault levels from the secondary of a transformer to the primary...

Smarter Electrical Distribution

The other day I came across an article in Technology Review on the development of a smart transformer. A professor at North Carolina State University is...

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...

Understanding electric motor insulation & temperature

Anyone specifying or using electric motors should have a basic understanding how the insulation is related to temperature. Three classes of insulation...

Always Use PPE

A lot of our members work in countries where PPE (personal protective equipment) is regulated or they work for companies/organizations which take employee...

8 Steps to Low Voltage Power Cable Selection and Sizing

A recurring theme on our forums is cable sizing. Now many installations are unique and require special consideration. However, a lot of the time things...

ANSI (IEEE) Protective Device Numbering

The widely used United Sates standard ANSI/IEEE C37.2 'Electrical Power System Device Function Numbers, Acronyms, and Contact Designations' deals with...

IEC 61439 - The Switchgear Standard

The new standard IEC 61439 replaces the old 60439. Compared to the old standard, the new 61439 is a more clearly defined and takes into account the assembly...

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...

Cable Sizing Software

When sizing cables nearly, everyone uses some form of software. This ranges from homespun spreadsheets to complex network analyses software. Each has its...

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