I am looking for firmware update for a Axpert Max 11000-48.

I bought this device mentionned "Original Axpert"

U1 : 73 03

U2 : 12 13

I am looking for firmware with smart fan control.

Not only the noise is really very disturbing, but I also have bad experience with the cold wet air continously blowing over the electronic components .

(northern maritime climate )

Thank you in advance with your help

On 2026/02/10 at 3:12 AM, Palawan said:

U1 : 73 03

I am looking for firmware with smart fan control.

Fan control doesn't seem to be Voltronics' strength. I have no idea which Max 11kW '28066 non-Twin firmware has the best fan control, but the latest is 73.83, see below.

There is also 73.78, a little older, available here with original (unpatched) and various patched versions for mitigating the "PV stuck at 90 V" issue.

This is main (U1) factory firmware version 73.83 for the Axpert Max 11kW '28066 non-Twin. Do not use with any other model or version.

Use at your own risk. The hex file is dated 29/May/2024.

Firmware upload instructions for models with a removable display.

This firmware does not process the QDOP command, so even with suitably recent display firmware, it will not support SoC% for settings 12,13, and 29 when connected to a suitable battery's BMS.

DSP_73.83-20250606T033303Z-1-001.zip

Edited February 23Feb 23 by Coulomb
Fixed(?) the firmware upload instructions link