Rockwell Automation T80008 Application Note MCB Discrimination - Manual

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AN-T80008
Issue 2 Feb 07 AN-T80008 1
Application Note
MCB Discrimination
In a radial feeder layout, as shown in Figure 1 overleaf, the purpose of discrimination is to disconnect
only the faulty load or feeder from the network and no others, thus ensuring maximum continuity of
service. If discrimination studies are not or are incorrectly carried out, an electrical fault may cause
several protective devices to trip, thus provoking an interruption in the supply of power to a large part of
the network. That constitutes an abnormal loss in the availability of electrical power for those parts of
the network where no fault occurred.
Issue Record
Issue
Number Date Revised by Technical
Check Authorised by Modification
1 Jun 06 Julia Bourn Initial Issue
2 Feb 07 Nick Owens Ray Brown Pete Stock Format