Siemens 6FC5372-0AA00-0AA2 Numerical Control Unit

Siemens 6FC5372-0AA00-0AA2 is the SINUMERIK 840D sl CNC hardware NCU 720.2 with an integrated PLC 317-2DP, designed to serve as the central control unit in SINUMERIK 840D sl systems. It provides CNC memory of 3 MB and PLC memory of 512 KB to support motion control and ladder logic programs, with internal heat dissipation engineered for reliable operation in machine tools. This NCU 720.2 PN is typically used as part of multi-axis CNC configurations on milling and turning machines running SINUMERIK 840D sl software, and Siemens lists it as a spare-part component with a documented replacement path to NCU710.1 (internal reference ID 90589419). The unit weighs approximately 3.6 kg and is built to integrate with the 317-2DP PLC, enabling compact packaging of CNC and PLC functions in a single hardware module. As a specific variant of the SINUMERIK 840D sl family, this 6FC5372-0AA00-0AA2 hardware supports standard NCU 720.2 functionality within the 840D sl ecosystem, and is commonly sourced for repairs, restorations, or upgrades of legacy 840D sl installations where the NCU 720.2 is the chosen control brain.