so you say its a code install. if a sparky has to work in the sub and wants to shut it down you have to throw the main? not a good install. for a $20 breaker is it not better to have a 2 pole breaker on the feeder to the sub? i still dont think this satisfies 240.21 as each ungrounded conductor requires an ocpd at the point it gets its supply. the main is a ocpd for the entire panel and acting as the service main not a feeder ocpd
