Hello,
National Instruments can configure a 500 input system consisting of 200 analog inputs and 300 digital inputs. In order to configure the best system for your application needs, we will need to gather further information on your application setup (such and signal ranges, acquisiton speed needed, etc.)
I would recommend contacting your National Instruments Field Sales Rep directly. You can find his information on our web site at:
For the Americas - http://www.ni.com/domestic_sales/
For Global offices - http://www.ni.com/niglobal/
They will be able to gather all the needed information, and configure the best system for your application/testing needs.
Michael Schneider
National Instruments
Applications Engineering