Hi. As per topic I'm looking for Sunmart IV Twin 6kw firmware. The current firmware loaded is 56.02 and I've tried to upgrade it with 56.xx available on this forum. It loaded with an error and now my inverter is bricked.

Can someone please share original sunmart firmware?

19 hours ago, Sebastian788 said:

I've tried to upgrade it with 56.xx available on this forum. It loaded with an error and now my inverter is bricked.

What exact firmware did you try to update it to?

Have you tried the techniques in If you think your inverter is bricked?

On 2025/04/20 at 10:25 AM, Coulomb said:

What exact firmware did you try to update it to?

Have you tried the techniques in If you think your inverter is bricked?

I've tried 56.72 from this link https://drive.google.com/file/d/1xeMlnAYGXQ8v7O-j6gIBgiLYeLFvQ06G/view

At the moment inverter is still accepting loading a firmware but it's failing every time. Even if i try to upload the same firmware it will fail in two different stages (ie first at 7% and then at second attempt at 23%), so maybe it's a problem with RS232 converter that I use (I'm using RJ45-DB9 cable supplied with inverter plus RS232 converter).

Sunmart company don't have any support at all. I think only option now is to get firmware from the same unit (somehow download it?) and then load it to my inverter.

13 hours ago, Sebastian788 said:

think only option now is to get firmware from the same unit (somehow download it?) and then load it to my inverter.

If it's stopping at different times, then any firmware update will fail the same. It's either the USB to RS-232 adapter, or the cable needs a resistor (see the files section, link in the post linked below), or it's slow opto couplers inside the inverter or its display.

You could also try the USB drive via a USB On The Go cable. That bypasses the serial electronics.

See the Firmware Upload Instructions for details.

Edited April 24, 20251 yr by Coulomb

OK. I'll try with the new RS-2323 converter. I'll report back.