Service OCD & Feeder OCD

[Bob Farron]

I recently looked at an installation where the overcurrent device at the service equipment protecting a feeder had a100 ampere rating protecting . The feeder is terminated into a 125 ampere overcurrent device protecting the feeder panelboard. While it does seem correct to me I can not find a section of the 2014 NEC that doesn't allow it. I would appericate your thoughts

 

[Smart $]

You won't find a section that says it isn't... or is permitted for that matter, at least not directly. What you will find is that feeder conductors and equipment must have an OCD protecting them at or below their rating.

 

[kwired]

I recently looked at an installation where the overcurrent device at the service equipment protecting a feeder had a100 ampere rating protecting . The feeder is terminated into a 125 ampere overcurrent device protecting the feeder panelboard. While it does seem correct to me I can not find a section of the 2014 NEC that doesn't allow it. I would appericate your thoughts

I can show you 100, 125 and even 200 amp main breaker panels supplied by a 60 amp feeder - there is no code violation if the calculated load is 60 amps or less (100 in your case). The panel is protected at or below it's rating, protecting it over it's rating is a problem.