We have a 7stop 2car group tac50/04 that the customer would like to add a card reader to the card and secure 3 floors. Seems to me the job had to be ordered with security from the factory and would have been sent out with a Security CNA card to do this? This job was not ordered with security as there are none of the car call lock out I/o’s. If the customer insists on securing the floors am I correct in my thinking that they will need new software and a CNA card? Anyone have any experience in adding security to a 50/04?

Not really. If you have 1 empty discrete port you can add the 7 CLO inputs and the SOA enable in the group on that port and make S10=3. Or just add the 3 CL_ inputs of the floors they want locked and make those high to secure the floor.

I’m not sure what you mean by discreet port? Would that then get wired into the IOC board not sure I want to risk their security equipment possibly shorting out something or causing issues with the IOC card?
Port 16 is empty on the car I/0s using the 8bit port menu.

Spare active low ports on the IOC on a TAC50-04:
Con 34 is Port 14
Con 35 is Port 15
Con 37 is Port 16