The 16 pin terminal base is the FP-TB-3. It is specifically designed for use with the FP-TC-120. The FP-TC-120 requires pins 1-16 for input channels 0-7. Pins 17-32 are not required. The FP-TC-120 will work with any of the FP-TB-X terminal bases.
Regards,
Aaron
LabVIEW Champion, CLA, CPI