Atleast thats what could be read in the docs
Maximum Array Size is upto 200 only.
You can use array pagination and increase the limit to any number of times.
This is wrong for configuration arrays. The total limit is 200. You can try to increase maximum value of the array control attribute over this limit, you will get the error message:
"For array control attributes, there should be a range check between 1 and 200."
The limit is also mentioned in the online help at Best Practices > Application Boundaries & Magic Numbers
A workaround solution for the configuration array limit of 200 rows could be to use System Configuration / BOM mapping rules.
A root model which contains the basic information, especially the total number of rows needed.
A sub model which is used with several instances. Each sub model instance handles up to 200 records in an array.