Siemens alarm 411503: Error in the hardware configuration
SINUMERIK PLC system alarm · Siemens 840D/810D powerline
What it means
The NCU type entered in the STEP 7 hardware configuration does not correspond to the real NCU in the rack. The PLC refuses to run against a wrong station description because peripheral addresses and system ranges would be misinterpreted. Download a hardware configuration containing the matching NCU type, then power the control OFF/ON.
Likely causes
- HW Config station built for a different NCU model (e.g. NCU 571 vs 572/710/720)
- Project reused from another machine without adapting the central hardware
- CPU slot article number edited manually
Triage note: Program continuation: switch control OFF - ON.
Need the part urgently?
Send us alarm 411503 with your machine details — typical RFQ turnaround is 24–48h.