Cincinnati Milacron 3 531 4531A HDCO PLC Slot Card

Cincinnati Milacron 3-531-4531A HDCO PLC Slot Card is a 16-point I/O circuit board that fits into an HDCO PLC system to expand the controller’s digital input/output capability. Identified by part number 3-531-4531A, this slot card is also cataloged in some listings as 35314531A. Marketed as a Cincinnati Milacron HDCO board and described in repair and refurbishment catalogs, the card is positioned as an I/O expansion module for Milacron’s HDCO PLC family. As a discrete PCB-based I/O slot card, it provides sixteen individual I/O points to extend the controller’s footprint without replacing the main CPU module. This makes it suitable for retrofitting or upgrading existing Milacron HDCO installations that require additional I/O channels. Various suppliers list this part under the Milacron HDCO board lineage and note its role as a replaceable, serviceable component within the HDCO ecosystem, reflecting its status as an active option for maintenance and inventory management of Milacron control systems.