Siemens alarm 25050: Axis %1 position monitoring / contour deviation too large
SINUMERIK axis monitoring alarm (hardware-consequential) · Siemens 840D/810D powerline
What it means
Actual position deviated from commanded contour beyond MD36400 - axis lagged or fought the command.
Likely causes
- mechanical binding (ways, gib, ballscrew nut)
- failed coupling or ballscrew bearing
- vertical-axis counterbalance failure
- failing drive delivering marginal torque (I2t reduction active)
- encoder scale damage giving false actual position
Triage note: Check preceding alarms in history: I2t/temperature alarms immediately before 25050 shift suspicion from mechanics to the drive.
Replacement parts
We supply the following units for this alarm — tested, warranty-backed:
- Request a quote →
ballscrew / linear-guide components per axis
axis mechanics · Common cause
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linear scale / encoder per axis
feedback · Common cause
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6SN1123-… / 6SL3120-…
power module (if torque starvation proven) · Check if others ruled out
Need the part urgently?
Send us alarm 25050 with your machine details — typical RFQ turnaround is 24–48h.