Siemens alarm 4090: Too many errors during power-up
SINUMERIK NCK general alarm · Siemens 840D/810D powerline
What it means
More than the permitted number of errors occurred while machine data was processed during control power-up, so the NCK suppresses further startup instead of continuing with an unreliable configuration. The individual errors are listed earlier in the power-up log/alarm history. Correct setting of the machine data is the remedy named in the Diagnostics Guide.
Likely causes
- Multiple inconsistent or out-of-range machine data after bad import
- Commissioning file from different software version loaded
- Corrupted SRAM contents following battery failure
Triage note: Review the power-up log, fix the underlying MD errors, then switch control OFF-ON.
Need the part urgently?
Send us alarm 4090 with your machine details — typical RFQ turnaround is 24–48h.