3401/3402/3407

DC overvoltage > Disconnect generator

SMA · Sunny Boy Solar Inverter

What does 3401/3402/3407 mean?

An overvoltage condition has occurred at the DC input, which poses a risk of destroying the inverter. This critical message is also signaled by rapid flashing of the LEDs, indicating an immediate need for intervention.

Common Causes

  • DC voltage exceeding the maximum input voltage of the inverter.
  • PV array has been incorrectly rated for the inverter.

Repair Steps & Checklist

Click steps to track your progress.

  1. 1

    Disconnect the inverter from all voltage sources immediately (refer to the inverter installation manual for the exact procedure).

  2. 2

    Check whether the DC voltage is below the maximum input voltage of the inverter.

  3. 3

    If the DC voltage is below the maximum input voltage of the inverter, reconnect the terminal block with the connected DC conductors to the inverter.

  4. 4

    If the DC voltage exceeds the maximum input voltage of the inverter, ensure that the PV array has been correctly rated or contact the installer of the PV array.

  5. 5

    If this message is repeated frequently, contact Service.

Browse all codes in this manual (23)
Verified technical data. Last updated: March 2026

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Source: SMA Sunny Boy Solar Inverter