Allen-Bradley 634486-90 REV-4 Memory Circuit Board

Allen-Bradley 634486-90 REV-4 Memory Circuit Board (PCB) is an open-style, mountable memory board used in AC drive systems. Identified in product literature and cross-references as a memory card/control board, the 634486-90 is commonly seen with the SP-634486-90 cross-reference and appears in multiple resale listings. The Rev-4 version is the specific revision noted on known inventory records, and manufacturing listings show the part as discontinued by the manufacturer, which means new units are no longer produced and current availability is primarily from used, refurbished, or aftermarket stock. Several listings describe the device as a memory module or memory circuit board for Allen-Bradley drives, underscoring its role as memory-related hardware within legacy drive backplanes. Buyers typically encounter this part when repairing older AB drive assemblies, where exact matching revision (Rev-4) and form factor (open style, mountable PCB) are essential for compatibility with existing backplanes and connectors.