Siemens 6FC5372-0AA00-0AA1 is a SINUMERIK 840D sl CNC hardware component—the NCU 720.2 PN with PLC 317-2DP—serving as the numerical control unit in SINUMERIK 840D sl systems. It provides CNC memory of 3 MB and PLC memory of 512 KB, with internal heat dissipation considerations for reliable operation. This PN/DP configuration (NCU 720.2 PN with PLC 317-2DP) is consistently listed in Siemens’ spare-part catalogs and device manuals for 840D sl configurations. Commonly purchased as a replacement spare part for SINUMERIK 840D sl installations.
