What is the maximum size branch breaker that can be installed in an NF panel with a 400a main breaker?
Max branch breaker in 400a NF
Largest amp size
The maximum branch mounted circuit breaker is 125 amp. One or two Powerpact J frame, 250 amp maximum, sub-feed breakers can be installed use sub-feed breaker kit NF600SFBJ and the proper back box and trim.