Selective Coordination Tools and Spreadsheets - Part One

[ali hassan]

I will focus in this study of selectivity Coordination on the
following main points:

Part One: What is selective coordination?

Part Two: NEC code and Selective Coordination

Part Three: Method of performing a selectivity coordination study:

First: By using Selective Coordination Time - Current Curves
second: By using Selective Coordination Charts/Tables.
By using Siemens calculators / spreadsheets.


Part One: What is selective coordination?


Selective coordination is a design requirement where only the
overcurrent device immediately upstream from the fault will operate,
minimizing the outage caused by the fault.

to read more, please follow the below link:

http://alihassanelashmawy.blogspot.com/2012/01/selective-coordination-tools-and.html