Low rated panelboard downstream to high rated circuit breaker

[dahualin]

Can we install a 200A panelboard with 150A main circuit breaker downstream to a 250A circuit breaker with 250A feeder? The distance is more than 100 feet. If we can or cannot, would you please point me to NEC article? Thank you.

 

[electrofelon]

Can we install a 200A panelboard with 150A main circuit breaker downstream to a 250A circuit breaker with 250A feeder? The distance is more than 100 feet. If we can or cannot, would you please point me to NEC article? Thank you.

Yes there is no restriction, as long as the conductors are protected and everything is appropriately sized for the load

 

[dahualin]

Yes there is no restriction, as long as the conductors are protected and everything is appropriately sized for the load

Thanks for your reply. My concern is the panel since it is rated 200A with 150A main circuit breaker. The upstream feeder circuit breaker is 250A. Do you think the panel needs protection from upstream circuit breaker?

 

[augie47]

The 150 amp main breaker will provide protection for the 200 amp panelboard. The conductors attached tot he 250 amp breaker need to be rated 250 amps or more other than any that comply with the 240.21 tap rules (or other Art 240 exceptions)

 

[electrofelon]

Thanks for your reply. My concern is the panel since it is rated 200A with 150A main circuit breaker. The upstream feeder circuit breaker is 250A. Do you think the panel needs protection from upstream circuit breaker?

Well this does sound like a violation of 408.36, but I am not really clear about the exact layout