EL
ErrorLib
Brands
||
  1. Home
  2. SEW Eurodrive
  3. MOVIMOT Field Distributor
  4. 21
About·Privacy·Terms

ErrorLib — Industrial Fault Code Library

Disclaimer: ErrorLib is an independent technical reference tool. While we aim for accuracy, always verify with the manufacturer’s official service manuals before performing maintenance on industrial equipment. ErrorLib is not affiliated with the brands listed.

21

Protection fault

SEW Eurodrive · MOVIMOT Field Distributor

What does 21 mean?

A CPU-related fault indicating that a protection mechanism within the inverter electronics has been triggered. This could be due to an internal hardware error or an attempt to perform an operation outside defined safety limits, causing communication to stop (DO=0).

Common Causes

  • Faulty inverter electronics components.
  • Errors during the execution of the system software.

Repair Steps & Checklist

Click steps to track your progress.

  1. 1

    Reset the fault by switching off the 24VDC supply voltage or using MOVILINK.

Browse all codes in this manual (30)
Verified technical data. Last updated: April 2026

Related Faults

01Overcurrent in output stage06Phase fault07DC link voltage too high
Source: SEW Eurodrive MOVIMOT Field Distributor
Open Manual (Page 32)Search more codes in this manual