The accuracy specifications for the FieldPoint modules are contained in the Operating Manuals. The Operating Manuals are found on the NI web site at NI Home > Support > Product Reference > Manuals > Current Revisions > Distributed IO > FieldPoint.
Generally, the error is specified as a an offset error plus a gain error. The offset error is a constant for the range (ppm of range) specified whereas the gain error is a percentage of the current input signal (ppm of reading).
Regards,
Aaron
LabVIEW Champion, CLA, CPI