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How do you size a circuit breaker or fusible switch for the primary or secondary of a transformer?

Issue:
How to select and size the Transformer Overcurrent Protection (OCP)
 
Product Line:
LV Transformers
 
Environment:
Applies to all SquareD/Schneider Electric Transformers
 
Cause:
Similar to other Electrical loads, Transformers often require Overcurrent Protection on the Secondary and/or Primary 

Resolution:
Reference the National Electrical Code (NEC) Table 450-3(b) along with the transformer`s Full Load Amperage (FLA or full load current) on the primary and secondary, and whether primary only or both primary and secondary OCP will be provided. 



 
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