Siemens 6FX1138-5BB04 is a SINUMERIK CPU/Control Board for the 810/820 CNC control family, serving as the central processing unit that drives motion control, I/O handling, and CNC logic within compatible Siemens systems. The module features a 16 MHz processor and is specified for SINUMERIK 810/820 configurations including GA3 and the 805SM variant, with ACOP and software version 2 as the documented baseline. It is commonly used as a CPU replacement or upgrade in aging SINUMERIK 810/820 installations to restore control performance and maintain compatibility with existing CNC software ecosystems.
