EL
ErrorLib
Brands
||
  1. Home
  2. Omron
  3. MX2 Inverter RS-485 Connection Guide
  4. #22
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.

#22

Function Not Allowed By Inverter State

Omron · MX2 Inverter RS-485 Connection Guide

What does #22 mean?

The Destination Device (inverter) rejected a function or write command because its current operational state or configuration prohibits the requested action. This is a protective mechanism, preventing changes that could interfere with active operations like RUN, auto-tuning, or changes to locked parameters (e.g., during Undervoltage conditions).

Common Causes

  • Attempted to modify a register that is configured as write-protected during the inverter's RUN state.
  • Issued an 'Enter' command while the inverter was actively running.
  • Attempted to write data to a register when the inverter was in a TRIP state (e.g., Undervoltage).
  • A 'soft lock' function is enabled on the target register, preventing modification.
  • Tried to change the function of an I/O terminal that is currently allocated for a critical, unchangeable role.
  • Attempted to change the contact type of a terminal specifically allocated for the Reset (RS) function.
  • Attempted to write data to a register while the inverter's auto-tuning function was actively running.
  • Tried to write data to a password-locked register without first providing the correct password for access.

Repair Steps & Checklist

Click steps to track your progress.

  1. 1

    Verify the inverter's current operating status (RUN, STOP, TRIP) before attempting to write to registers or change settings. If modification requires STOP, ensure the inverter is commanded to STOP.

  2. 2

    Check if the soft lock function is enabled for the target register and disable it if necessary before attempting to write.

  3. 3

    Enter the correct password for password-protected registers prior to attempting any write operations.

  4. 4

    Confirm that auto-tuning is not active when attempting to write to related registers. Wait for auto-tuning to complete or disable it.

  5. 5

    Review I/O terminal assignments. Do not attempt to reconfigure terminals that are fixed or allocated to critical functions like Reset (RS) during operation.

Browse all codes in this manual (15)
Verified technical data. Last updated: April 2026

Related Faults

#01Unsupported Function Code#02Invalid Modbus Address#03Invalid Modbus Data Format
Source: Omron MX2 Inverter RS-485 Connection Guide
Open Manual (Page 59)Search more codes in this manual