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When is arc-flash mitigation required by the NEC?

Issue:
NEC and Arc-Flash Mitigation

Product Line:
Circuit Breakers

Environment:
Powerpact and Masterpact

Resolution:
In the 2017 edition of the NEC, article 240.87, arc energy reduction is required where the highest continuous current trip setting for which the actual overcurrent device installed in a circuit breaker is rated or can be adjusted is 1200 A or higher.  This means that even if an electronic trip circuit breaker with a 1200 A sensor has its current rating switch set to, for example, 0.75 (900 A), it will still require an arc energy reduction means.  If the overcurrent device in the circuit breaker meets this criterion, then documentation and a method to reduce the clearing time must be provided.  

Please see attached data bulletin for more information.

For information on the Schneider-approved arc flash mitigation system, ERMS, please see second attachment.
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