22 hex

Modbus Exception: Function Not Allowed (Inverter State Specific)

Omron · MX2 Series Type V2 Compact Inverter

What does 22 hex mean?

This Modbus exception indicates that the inverter cannot perform the requested function due to its current operating state or configuration. This includes attempts to change RUN-protected parameters during operation, issue an Enter command while the inverter is in RUN or trip status, write to soft-locked or password-protected registers, or modify fixed I/O terminal settings. It's a broad category of operational constraints.

Additional Steps

Steps 1–2 are listed in Priority Fix.

  1. 3

    Avoid issuing the 'Enter command' (0900 hex) or writing to registers during auto-tuning, RUN mode, or when a trip is active.

  2. 4

    Ensure that attempts to change I/O terminal settings or contact types are made only when allowed by the inverter's operating mode and configuration (not fixed or read-only).

Source: Omron MX2 Series Type V2 Compact Inverter
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