You are misinterpreting the Square D series ratings.
You may series rate only two devices, but they do not have to be electrically consecutive. If the 22K main breaker series rates with a downstream 10K breaker it makes no difference how far downstream the breaker is or if there are additional breakers in between them.
What you can not do is use one valid series rating to "feed" another series rating, such as: Main 400A LA 42K in series with a feeder 200A QD 25K which is then in series with a branch 20A QO 10K.
[This message has been edited by JBD (edited 07-30-2004).]
