RFQ turnaround 24–48h · inbound queries only
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Fagor alarm 4187: ERROR 821: Image capturing sensor (CCD) error

CNC 8055 SERCOS drive error (DDS) · Fagor DDS drives

What it means

The CCD/LED scanning unit inside the encoder or scale reader head reports self-test failure.

Likely causes

  • LED illumination end-of-life (years of duty)
  • CCD die cracked by shock/vibration
  • internal condensation/corrosion in head housing

Triage note: Heads are sealed units - no field CCD repair. Order complete scale or head per series documentation; record distance-coded vs single-mark variant before ordering.

Replacement parts

We supply the following units for this alarm — tested, warranty-backed:

  • S2OX/S2X series (match travel)

    Linear scale assembly with new scanning head · Primary suspect

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  • SP-1024-R-C5-IP66

    Rotary encoder (if fault on rotary feedback) · Common cause

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Need the part urgently?

Send us alarm 4187 with your machine details — typical RFQ turnaround is 24–48h.

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