What is the maximum circuit breaker I can use to feed a sub panel from a 100 amp panel?

Question

If possible can you give the part of the electrical code that gives this

Answer 1

The Code isn't the thing that sets the limit.

There's a 100 A. breaker protecting the whole system.

That limits the total draw you can place on that panel.

You can even tap the buss at 100A.

Be careful though.

Whatever you add might overload that main breaker.

(If you have added area to the building, the Code might

require a larger service per Sect.220).

Most residences now get 150A. service as a minimum.

Answer 2

Well do the math. Figure out the total amp draw your house uses at any given time. Then subtract that from 100 amps. Whatever you come up with would be the approximate number. Or you could do it the redn@ck way and shut down everything in the house to use your sub panel toys.  

Answer 3

Call a qualified professional electrician. They get paid to do the job properly. Some answers given on this site are dangerous, if not lethal. It will depend on the size of the sub panel. If it is a 60 amp buss then 60 amp is the maximum feed size, if you use 50 amp feed the wire must be a 50 amp wire which is a 6 not a 10.  Call a qualified professional electrician.