The question actually pertains to the 'readily accessibility' of a circuit breaker so the ideal 1st place to look is in the Index under "Circuit breakers" on page 70-789 of the 2008 NEC. The first thing that comes up is Article 240. If you browse through that, you'll come to "accessibility" at 240.24.
looking down a bit farther in the Index under "Circuit breaker" one finds "Accessibility and grouping" which directs one to 404.8 which answers the question again.
It's all in familiarizing oneself with the Index and reducing the question to the proper code language.:smile:
Welcome to the Forum.
If your jurisdiction is referencing the 2002 NEC or any previous version and the circuit breaker is not being used as a switch, then there is no maximum height for the circuit breaker.
(NYS is referencing the '02 for residential work)
In the '08 NEC, they addded 240.24(A) which restricts the height of a circuit breaker to 6ft-7in.