The FX5-4AD-TC-ADP: Don't confuse this with the FX5-232ADP, which is a serial comms adapter. The 4AD-TC-ADP is a dedicated thermocouple input module; won't work as a drop-in for a 232 card, and vice versa. If you need temperature measurement on an FX5 system, this is the part.
No occupied I/O points — it's an adapter, not a main CPU slave, so your point count stays untouched. Conversion speed clocks in about 85 ms per channel, fine for trend logging; don't plan a fast PID loop at that rate. Photocoupler isolation between the module and CPU keeps the backplane noise-free, but channels are non-isolated from each other — they share a common reference. Fine when all thermocouple junctions ride on the same ground potential, but watch for floating junctions tied to separate earths.