Siemens 6FX1820-0AX01 Printed Circuit Board Assembly

Siemens 6FX1820-0AX01 Printed Circuit Board Assembly is a SINUMERIK 3T CNC control board designed to drop into the 6FX1 126-0BD00 module slot within legacy SINUMERIK 3T installations, providing a ready-to-swap PCB replacement that technicians use to restore machine control without replacing an entire controller. The board houses four 27256 EPROM devices that store the 4B Basic software/firmware, delivering the core motion control routines, I/O interfacing, and other CNC control functions that older SINUMERIK systems rely on for basic operation and program execution. With an approximate weight of 0.13 lb, the PCB is compact enough to be listed as a spare part in CNC repair catalogs and is frequently sold as a used or refurbished item by suppliers specializing in SINUMERIK parts, reflecting its role as a legacy replacement component. In spare-part catalogs and repair listings, the reference is consistently identified as 6FX1820-0AX01, a circuit board assembly rather than a standalone controller module, underscoring its function as a drop-in replacement within the SINUMERIK 3T ecosystem for mills and turning centers that continue to rely on this legacy hardware.