100% Rated Main Breaker?

[Jraef]

Jraef, I question some of this. First I have a hard time believing that I cant get and use 100% breakers for feeders or branch circuits in panelboards. For example. L frame breakers for I line are available in 100%. Also, I understand it is the Assembly that needs to be 100% rated, but I imagine that manufacturers have approved combinations and I could add a 100% breaker to an existing panelboard if it met the requirements for space, other breakers, etc. Correct me if I am wrong, this is somewhat assumed from what I see in manufacturers breaker and panelboard catalogs....

Yes you can get an L frame breaker for an I-Line panel that is rated for 100%, but only as the Main breaker, not feeders, just like any other mfr. But call your friendly neighborhood Schneider dealer if you don't believe me. You can also get a stand-alone enclosed circuit breaker rated for 100% that you can use as a feeder, if it is fed FROM feed through lugs on another panel. But you will not find feeders in a panel that are 100% rated. There needs to be a minimum amount of air space around the breaker to attain that 100% rating and if it's a feeder in a panel where another breaker can be mounted right next to it, then it can't qualify.