SINUMERIK 840D/DE NCU 573.2 Pentium II without system software memory: NC 2.5 MB, PLC 96 KB PROFIBUS DP prepared SIEMENS 6FC5357-0BB53-0AE1 SIEMENS 6FC53570BB530AE1 SINUMERIK 6FC5357-0BB53-0AE1 6FC53570BB530AE1 6FC5357-0BB53-0AE1