A591

Drive HW initialization

ABB · ACS580

What does A591 mean?

The drive's hardware is undergoing its initialization process. While typically a brief startup event, persistent initialization can signal a deeper issue with the drive's hardware or firmware. The auxiliary code might provide more context on the specific stage of initialization.

Common Causes

  • Failure of a specific hardware component to respond during its self-test phase (e.g., an internal measurement ASIC, gate driver).
  • Issues with the internal clock synchronization or timing circuits on the control board.
  • Firmware corruption affecting a fundamental part of the hardware initialization routine.
  • An attempt to boot with an incompatible power unit or control board combination.
  • Persistent internal memory error preventing the drive from completing its boot sequence.

Repair Steps & Checklist

Click steps to track your progress.

  1. 1

    Execute a drive power cycle.

  2. 2

    Perform a full parameter reset to factory defaults (P96-01=1) to clear any potentially corrupt configuration that might interfere with initialization.

  3. 3

    Update the drive's main firmware to the latest compatible version.

  4. 4

    If option modules are present, power down the drive and remove them one by one to see if the fault clears, indicating an issue with a specific module.

  5. 5

    If the issue persists after these steps, the drive's main control board likely requires replacement.

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Verified technical data. Last updated: March 2026

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