Siemens alarm 611U-F504: Measuring circuit error, motor measuring system
SIMODRIVE 611U drive alarm · SIMODRIVE 611D/611U
What it means
The motor encoder signal level is too low, disturbed (screening), or cable-break monitoring responded. On HRS variants with 1Vpp encoders this message can also appear benignly during a controlled shutdown where only the drive's supply was switched off separately.
Likely causes
- non-original or damaged encoder cable (use preassembled Siemens cables)
- intermittent contact from cable-drag motion, crushed connector
- shield not clamped under the top screw of the control module faceplate
- toothed-wheel encoder gap out of tolerance
- defective encoder or control module
Replacement parts
We supply the following units for this alarm — tested, warranty-backed:
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6FX2002-…
cable · Primary suspect
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per fitted encoder
encoder · Common cause
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6SN1118-…
control-board · Check if others ruled out
Need the part urgently?
Send us alarm 611U-F504 with your machine details — typical RFQ turnaround is 24–48h.