On 2025/11/18 at 6:01 AM, add1c7ed55 said:

Can you modify this 78.08 derate 450v to be parched with 90v block with 200v too? Like 278.07.

This is patched firmware versions x78.08, based on factory firmware version 78.08 for the Axpert max E 11kW '28066 Twin. Do not use with any other model. The original hex file is dated 2024/6/24.

This firmware works around the "stuck at 90 V" problem by changing the current threshold from 0.50 A to 0.10 A. It also fixes the premature float bug, and changes the reported version number to x78.08 (e.g. 278.08). The removable display will continue to show version U1 78 08.

As is usual lately, there is a 200V version (278.08), a 150V version (178.08), and a 90V version (978.08), as well as the original factory version (dsp_original_78.08.inv).

These versions do not modify the derate at 360 V behaviour. [ Edit February 2026: I was confused! These DO have the current limit set to start at a PV voltage of 450 V, which is the patched behaviour, since I started with cuba.cz's already-patched binary, and added my "stuck at 90V" etc patches to that. Factory firmware starts the 100A charge current limit at 360 V. Sorry for the confusion! ]

I note that 78.08 has a completely different EEPROM address layout compared to 78.07, so do not use this version, or 78.09, if your inverter came with 78.07. As far as I can tell, 78.08 and 78.09 use the same address layout, so you could go straight to x78.09 patched firmware if you are on factory 78.08 now. I produce both just in case there is some hidden difference, and to give users the choice.

Use at your own risk; I cannot test this firmware as I do not own an Axpert Max. It has been "sanity checked" by disassembling the firmware and confirming that the intended changes are present.

Firmware upload instructions. https://forums.aeva.asn.au/viewtopic.php?p=87767#p87767

dsp_x78.08_patched.zip

Edited February 17Feb 17 by Coulomb

These are patched firmware versions x78.09, based on factory firmware version 78.00 for the Axpert max E 11kW '28066 Twin. Do not use with any other model. The original hex file is dated 2024/11/04.

This firmware works around the "stuck at 90 V" problem by changing the current threshold from 0.50 A to 0.10 A. It also fixes the premature float bug, and changes the reported version number to x78.09 (e.g. 278.09). The removable display will continue to show version U1 78 09.

As is usual lately, there is a 200V version (278.09), a 150V version (178.09), and a 90V version (978.09), as well as the original factory version (dsp_original_78.09.inv).

This version does not modify the derate at 360 V behaviour. I note that 78.09 has a completely different EEPROM address layout compared to 78.07, so do not use this version, or 78.08 (patched or factory), if your inverter came with 78.07. As far as I can tell, 78.08 and 78.09 use the same address layout, so you could go straight to x78.09 patched firmware if you are on factory 78.08 now. I produce both just in case there is some hidden difference, and to give users the choice.

Use at your own risk; I cannot test this firmware as I do not own an Axpert Max. It has been "sanity checked" by disassembling the firmware and confirming that the intended changes are present.

Firmware upload instructions. https://forums.aeva.asn.au/viewtopic.php?p=87767#p87767

Edit: "derate at 450 V" → "derate at 360 V"

dsp_x78.09_patched.zip

Edited February 17Feb 17 by Coulomb

10 hours ago, Coulomb said:

These are patched firmware versions x78.09, based on factory firmware version 78.00 for the Axpert max E 11kW '28066 Twin. Do not use with any other model. The original hex file is dated 2024/11/04.

This firmware works around the "stuck at 90 V" problem by changing the current threshold from 0.50 A to 0.10 A. It also fixes the premature float bug, and changes the reported version number to x78.09 (e.g. 278.09). The removable display will continue to show version U1 78 09.

As is usual lately, there is a 200V version (278.09), a 150V version (178.09), and a 90V version (978.09), as well as the original factory version (dsp_original_78.09.inv).

This version does not modify the derate at 450 V behaviour. I note that 78.09 has a completely different EEPROM address layout compared to 78.07, so do not use this version, or 78.08 (patched or factory), if your inverter came with 78.07. As far as I can tell, 78.08 and 78.09 use the same address layout, so you could go straight to x78.09 patched firmware if you are on factory 78.08 now. I produce both just in case there is some hidden difference, and to give users the choice.

Use at your own risk; I cannot test this firmware as I do not own an Axpert Max. It has been "sanity checked" by disassembling the firmware and confirming that the intended changes are present.

Firmware upload instructions. https://forums.aeva.asn.au/viewtopic.php?p=87767#p87767

I tried to attach the zip file... All good now.

dsp_x78.09_patched.zip

11 hours ago, Coulomb said:

Acestea sunt versiuni de firmware x78.09 actualizate, bazate pe versiunea de firmware 78.00 din fabrică pentru Axpert max E 11kW '28066 Twin. Nu utilizați cu niciun alt model. Fișierul hexadecimal original este datat 04.11.2024.

Acest firmware rezolvă problema „blocat la 90 V” prin modificarea pragului de curent de la 0,50 A la 0,10 A. De asemenea, remediază eroarea de tip „premature float” și schimbă numărul versiunii raportat la x78.09 (de exemplu, 278.09). Ecranul detașabil va continua să afișeze versiunea U1 78 09.

Ca de obicei în ultima vreme, există o versiune de 200V (278.09), o versiune de 150V (178.09) și o versiune de 90V (978.09), precum și versiunea originală din fabrică (dsp_original_78.09.inv).

Această versiune nu modifică comportamentul de reducere a puterii la 450 V. Am observat că 78.09 are o structură complet diferită a adreselor EEPROM față de 78.07, așa că nu utilizați această versiune sau 78.08 (cu patch-uri sau din fabrică) dacă invertorul dvs. a venit cu 78.07. Din câte îmi dau seama, 78.08 și 78.09 folosesc aceeași structură de adrese, deci ați putea trece direct la firmware-ul cu patch-uri x78.09 dacă sunteți acum pe 78.08 din fabrică. Le produc pe amândouă în cazul în care există vreo diferență ascunsă și pentru a oferi utilizatorilor posibilitatea de a alege.

Folosește pe propriul risc; nu pot testa acest firmware deoarece nu dețin un Axpert Max. A fost „verificat” prin dezasamblarea firmware-ului și confirmarea faptului că modificările dorite sunt prezente.

Instrucțiuni pentru încărcarea firmware-ului. https://forums.aeva.asn.au/viewtopic.php?p=87767#p87767

Am încercat să atașez fișierul zip... Acum totul e în regulă.

<font dir="auto" style="vertical-align: inherit;"><font dir="auto" style="vertical-align: inherit;">dsp_x78.09_patched.zip</font></font>

Thanks a lot. I have 2 questions.

1. What can happen if i flash the 78.09 on an inverter that comes with 78.07 oem.?

2. I have an inverter with 78.07 and another with 78.09, can i paralelize them to work in parallel? Will work good or will have problems of syncronizing?

10 hours ago, add1c7ed55 said:

What can happen if i flash the 78.09 on an inverter that comes with 78.07 oem.?

The EEPROM will be all messed up. You will likely lose accuracy of measurements, and you might end up with fault code 90 eventually. I highly don't recommend this.

I have an inverter with 78.07 and another with 78.09, can I parallelise them to work in parallel? Will work good or will have problems of synchronising?

I believe that it will work. The main problem with paralleling inverters with slightly different firmware versions is if they change the CAN bus message layout. This only happens rarely. Sadly I don't have the time to check this at present by comparing key parts of the firmwares. It's a quite tedious process, working with assembly language.

It might be possible to run the inverters both with the output mode set to PAR, yet without actually paralleling the inverters, for a while. Make changes to settings, make sure that everything seems to work, and check that the difference between outputs is 20 VAC or less, preferably under 5 VAC. Use one multimeter with a lead on each active output for this. It's been a long time since I played with paralleling, so I can't be sure that the inverters won't complain about this.

On 25.11.2025 at 0:20, Coulomb said:

Memoria EEPROM va fi complet defectă. Probabil vei pierde precizia măsurătorilor și s-ar putea să ajungi în cele din urmă la codul de eroare 90. Nu recomand cu căldură acest lucru.

Cred că va funcționa. Principala problemă cu conectarea în paralel a invertoarelor cu versiuni de firmware ușor diferite este dacă acestea modifică structura mesajelor de pe magistrala CAN. Acest lucru se întâmplă rar. Din păcate, nu am timp să verific acest lucru în prezent comparând părți cheie ale firmware-urilor. Este un proces destul de plictisitor, lucrând cu limbaj de asamblare.

Ar putea fi posibil să rulați invertoarele atât cu modul de ieșire setat pe PAR, cât și fără a le conecta efectiv în paralel, pentru o perioadă. Faceți modificări la setări, asigurați-vă că totul pare să funcționeze și verificați dacă diferența dintre ieșiri este de 20 V CA sau mai puțin, de preferință sub 5 V CA. Folosiți un multimetru cu un cablu pe fiecare ieșire activă pentru aceasta. A trecut mult timp de când nu am mai încercat conectarea în paralel, așa că nu pot fi sigur că invertoarele nu se vor plânge de asta.

I connected them on parallel. Works well, 50%-50%...different firmware.

This is patched firmware version 378.08, based on factory firmware version 78.08 for the Axpert max E 11kW '28066 Twin. Do not use with any other model. The original hex file is dated 2024/6/24.

This firmware has two sets of patches: the "derate at 450V" patches, and the "stuck at 90V" work arounds, with minimum MPPT voltage set to 200 V. So this will suit only a few people!

This firmware works around the "stuck at 90 V" problem by changing the current threshold from 0.50 A to 0.10 A. It also fixes the premature float bug, and changes the reported version number to 378.08. The removable display will continue to show version U1 78 08.

There is only a 200V version for this particular combination of patches. Also in the zip file are the original factory firmware, and firmware only patched for derating at 450V, for convenience.

Use at your own risk; I cannot test this firmware as I do not own an Axpert Max. It has been "sanity checked" by disassembling the firmware and confirming that the intended changes are present.

Firmware upload instructions. https://forums.aeva.asn.au/viewtopic.php?p=87767#p87767

dsp_378.08_patched_200V_derate450V.zip

This is main (U1) factory firmware version 64.69 for the Axpert Max 11kW '2809 Twin. Do not use with any other model or version.

Use at your own risk. The hex file is dated 18/10/2023.

Firmware upload instructions for models with a removable display.

This firmware processes the QDOP command, so with suitably recent display firmware, it should support SoC% for settings 12,13, and 29 when connected to a suitable battery's BMS.

MAXE11K_TWIN_6469.7z

Hello, young people! After several 
updates of friends and acquaintances 
of Easun inverters, it's time to 
update my Easun smw11 kw inverter. 
My first one was with 64. 03 and I 
updated it with 64.62 and it works like 
a clock. However, the second one is 
78.09 and the MPPT controller does 
not wake up and I decided to update it 
with a patched firmware too, but by 
mistake my daughter pulled the cable 
and accordingly stopped the update in 
the middle. Now it flashes 32! and it 
doesn't work. It doesn't let me 
reflash with the cable in the kit. I try 
with a USB flash drive, but it says 
error 003 (wrong format). Could you 
advise me how to proceed?

Edited February 24Feb 24 by pecov

17 hours ago, pecov said:

Could you advise me how to proceed?

See If You Think Your Inverter is Bricked. Basically, you need to have faith, try many times, and perhaps vary the timing.

2 hours ago, Coulomb said:

Виж дали мислиш, че инверторът ти е блокиран. По същество трябва да имаш вяра, да опитваш много пъти и може би да променяш времето.

Today I decided to try a different way. I turned off the power supply and discharged the capacitors.

I ran it only on the city network and with a simple old telephone cable I connected the laptop

to the inverter display. I ran only on the city network and while it was counting the seconds

I gave it an update and it started. Everything is fine now, everything works with the patched

firmware 278.09. Thank you very much for all the patched firmware you do. I appreciate it.

I have repaired the MPPT controllers of quite a few friends and acquaintances. Thanks again!

Edited February 24Feb 24 by pecov

Hi @Coulomb , in a previous post of mine I asked you for help like this "Hi Coulomb, I'm new to the forum and I think you're one of the wisest.

I have a problem with my 2 inverters connected in parallel.

They are the SMW 11KW 48V Easun/POWLAND model, these in short https://amzn.to/4cUGdMH

Early in the morning they stop at 90V, I think they suffer from what I read here ("90V bug").

If I disconnect and reconnect the differentials in the string boxes, the voltage rises to 270V for each of the 4 strings I have.

The firmware for both inverters are U1 64.09 and U2 38.14. "

Unfortunately, I haven't been able to update since then, and now I'd like to try because the 90V lockout problem and the possible 100A charge limit are bothering me.

I have two questions:

1. What are the most up-to-date and stable versions of the patches you've created?

2. I'm about to replace my old AGM batteries with two 2P16S battery packs up to 30kWh and two separate JK BMSs. With your patches, is it better to set them on the inverters with User parameters or connect one of the two BMSs?

Thanks so much for your support.

Edited February 25Feb 25 by cjb

10 hours ago, cjb said:

Здравейте @Coulomb , в предишен мой пост те помолих за помощ като този: "Здравей, Кулон, нов съм във форума и мисля, че си един от най-мъдрите.

Имам проблем с двата ми инвертора, свързани паралелно.

Това са моделът SMW 11KW 48V Easun/POWLAND, които са накратко https://amzn.to/4cUGdMH

Рано сутрин спират на 90V, мисля, че страдат от това, което прочетох тук ("90V бъг").

Ако изключа и свържа отново диференциалите в кутии със струни, напрежението се повишава до 270V за всяка от четирите струни, които имам.

Фърмуерът и за двата инвертора е U1 64.09 и U2 38.14. "

За съжаление, оттогава не съм успял да обновявам и сега искам да пробвам, защото проблемът с заключването на 90V и възможният лимит на заряд от 100A ме притесняват.

Имам два въпроса:

1. Кои са най-актуалните и стабилни версии на пачовете, които сте създали?

2. Предстои ми да заменя старите си AGM батерии с два 2P16S батерийни пакета до 30kWh и два отделни JK BMS. При твоите пачове, по-добре ли е да ги настроиш на инверторите с потребителски параметри или да свържеш някой от двата BMS?

Много благодаря за подкрепата.

I apologize for interfering, but I have direct oversight of this particular firmware.

On one of my inverters I had factory firmware 64.03 and I had the problem with it getting

stuck at 90 volts. I uploaded patch 264.62 prepared by @Coulomb and since then the inverter

has worked wonderfully. The MPPT controller starts as soon as the current passes 0.2 amps

and the yield has increased significantly. I charge the batteries from solar energy with

145 amps. It also works great in cloudy weather. I have uploaded this patch to several inverters

and everything is fine. Be careful with the cables when uploading the firmware. Good luck!

Thanks Pecov, is this 264.62 the latest available update?

Can I ask you a favor? Can you tell me the files and the correct procedure? Maybe there's another post I should follow.

Edited February 26Feb 26 by cjb

3 hours ago, cjb said:

Благодаря, Пеков, това 264.62 ли е най-новата налична актуализация?

Мога ли да те помоля за услуга? Можеш ли да ми кажеш файловете и правилната процедура? Може би има друг пост, който трябва да следя.

Hi CJB. The latest patch, I think it's 64.69 and it's uploaded a little higher in this post, but I haven't tried it and I can't tell you how it behaves. Otherwise, I'm sure about patch 264.62, because in addition to one of my inverters, I've uploaded it to 15 other machines and they all work great. Instructions for uploading the firmware are in the other forum, and I downloaded the firmware from here. Read the instructions carefully and be careful not to mess with the cables. Good luck!

instructions-PIP-5048MK inverter - Page 20 - AEVA Forums

I recommend you also read this topic on the forum-Firmware Axpert Max Twin 11K - Page 5 - Inverters - Power Forum - Renewable Energy Discussion

Thank you

On 2026/02/25 at 9:13 PM, cjb said:

What are the most up-to-date and stable versions of the patches you've created?

I create many patches, for a wide variety of Voltronic inverter models.

The most recent set is x78.10, which has the "stuck at 90V" issue worked around, and optionally also or only the 100 A charge current limit threshold changed from 360 V to 450 V. But it won't work for your inverters, which have the '2809 processor, and 78.10 is for the '28066 processor.

The latest patched x64.xx firmware set is indeed x64.62, available here with instructions. Unfortunately, 64.62 (on which the x64.62 patched versions are based) is a month older than the 64.09 that you have now. There is also factory (not patched) firmware version 64.69, which is 2 months more recent than 64.09, but I have not patched it at present.

Also unfortunately, x64.62 does not patch the 100 A charge limit threshold. This is a fairly recently discovered issue, so there are only a few patched firmwares that implement it.

On 2026/02/25 at 9:13 PM, cjb said:

I'm about to replace my old AGM batteries with two 2P16S battery packs up to 30kWh and two separate JK BMSs. With your patches, is it better to set them on the inverters with User parameters or connect one of the two BMSs?

I don't know the JK BMSs. If they talk a protocol that the Voltronic inverters support (e.g. Pylontech etc), then you could use that battery type with the inverters. They would also have to talk to each other, to get the maximum charge current correct for two paralleled strings of cells. Otherwise, you'll have to choose the USEr battery type, and forgo the ability to protect individual cells going over- or under-voltage.

If there is enough call for it, I could patch 64.69 the same as I did 78.10. That would be the latest firmware available in the 64.xx series, and would optionally change the 100A current limit PV voltage threshold.

Edited March 1Mar 1 by Coulomb

Thanks so much, @Coulomb ! I updated to x64.62 and everything seems to be working great. I no longer have the 90V lockout, now they get 180V in the morning! I only have an annoying F60 error that occurs when the house requests more than 7kW, but that's probably due to the crappy batteries I still have. It would be great to have the latest firmware version with all your best tweaks. Thanks again!

On 2026/03/01 at 6:17 AM, Coulomb said:

I create many patches, for a wide variety of Voltronic inverter models.

The most recent set is x78.10, which has the "stuck at 90V" issue worked around, and optionally also or only the 100 A charge current limit threshold changed from 360 V to 450 V. But it won't work for your inverters, which have the '2809 processor, and 78.10 is for the '28066 processor.

The latest patched x64.xx firmware set is indeed x64.62, available here with instructions. Unfortunately, 64.62 (on which the x64.62 patched versions are based) is a month older than the 64.09 that you have now. There is also factory (not patched) firmware version 64.69, which is 2 months more recent than 64.09, but I have not patched it at present.

Also unfortunately, x64.62 does not patch the 100 A charge limit threshold. This is a fairly recently discovered issue, so there are only a few patched firmwares that implement it.

I don't know the JK BMSs. If they talk a protocol that the Voltronic inverters support (e.g. Pylontech etc), then you could use that battery type with the inverters. They would also have to talk to each other, to get the maximum charge current correct for two paralleled strings of cells. Otherwise, you'll have to choose the USEr battery type, and forgo the ability to protect individual cells going over- or under-voltage.

If there is enough call for it, I could patch 64.69 the same as I did 78.10. That would be the latest firmware available in the 64.xx series, and would optionally change the 100A current limit PV voltage threshold.

I use 264.62 and I have no problem with charging from a 145 amp photovoltaic system. I haven't tried it on the grid because I'm completely off grid. My inverter looks like this, but it's still a copy of Voltronic. I've also uploaded the patch to a few other inverters that look like this and their charging current is over 130 amps.

https://www.panpowersolar.com/products_details/19.html

Thanks a lot. I think I'm starting to get confused with the versions. I installed the one @Coulomb reported at https://powerforum.co.za/topic/17487-firmware-axpert-max-twin-11k/page/5/#findComment-210250. Is your 264.62 the same or something else?

On 2026/03/04 at 11:06 AM, cjb said:

Thanks a lot. I think I'm starting to get confused with the versions. I installed the one @Coulomb reported at https://powerforum.co.za/topic/17487-firmware-axpert-max-twin-11k/page/5/#findComment-210250. Is your 264.62 the same or something else?

This is exactly the patch I use. It works perfectly for me.