Rockwell Automation T80008 Application Note MCB Discrimination - Manual (Page 5)

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AN-T80008 MCB Discrimination
Issue 2 Feb 07 AN-T80008 5
Conclusion
The internal self-protection of T824x power units may cause them to trip before the MCBs. Ensure that
MCBs and other circuit protection devices are rated to ensure that any one short will not overload the
supply. Low current ratings are therefore recommended, to ensure that the protection device trips first,
due to its time/current curve.