Here are more HEX File Only Packages of (DSP / Main CPU / U1) firmware for VM III TWIN and VM IV TWIN.

An updated list of available packages in this thread can be found in the very first post at:
https://powerforum.co.za/topic/29708-collection-of-dsp-axpert-firmware-for-vm-iii-twin-and-vm-iv-twin/

CREDITS: Original uploaders of the attached firmware files:

@mhd_murad DSP version 60.95 dated 2024/01/16
Link to original package post

@Nabeel Raza DSP version 84.00 dated 2024/06/09
Note: Quiet fans control logic is not available in this version + I copied this firmware's full package from the uploader's Google Drive
Link to original package post

USE AT YOUR OWN RISK, NO GUARANTEES WHATSOEVER!

DSP Reflash Tool is always available in the very first post of this thread at:
https://powerforum.co.za/topic/29708-collection-of-dsp-axpert-firmware-for-vm-iii-twin-and-vm-iv-twin/

Detailed instructions of how to update/reflash firmware of Removable and Round Display inverter models, posted by @Coulomb at:
https://forums.aeva.asn.au/viewtopic.php?p=87767#p87767

If you think your inverter is bricked, there are a number of helpful tips posted by @Coulomb at:
https://forums.aeva.asn.au/viewtopic.php?p=59897#p59897

Enjoy!

 

 

Additionally, here is the full package for display (MCU / Secondary CPU / U2) firmware version 39.26 for VM IV TWIN only (with round display), as @Nabeel Raza uploaded it to his Google Drive, and not as an attachment in his post at:
https://powerforum.co.za/topic/29708-axpert-firmware-collection-for-vm-iii-and-vm-iv-twin-models-only/page/4/#comment-207455

VM TWIN (III & IV) DSP 60.95 hex.zip VM TWIN (III & IV) DSP 84.00 hex.zip VM TWIN_84.00.7z VM IV Panel_Reflash_MCU_39.26.zip

 

Edited October 27, 20241 yr by Tarek Yag
Added bricking help + Improved text layout

Hi

VMIII 6kw twin.FW 60.95

Never go to bulk 55V. Go to float 54.5 and current go down gradually .

Is that premature float bug ???

2 hours ago, bratpit said:

Never go to bulk

I have this exact problem but with VM IV Twin 4000 which is 24 V, but it's not only on PV charging but also AC. However, it didn't start with the version you reported, it's been around for a few months and I've always believed it's a hardware fault.

Whenever it starts charging, it keeps charging until it reaches float voltage, then switches to float mode, hence, current go down gradually. So, I had to set float voltage the same as bulk voltage, at least until I fix my BMS firmware bug, to make a successful connection between my BMS and inverter. Although it took too long, but my settings are safe for my own setup.

Edited July 29, 20241 yr by Tarek Yag

2 hours ago, Tarek Yag said:

 but it's not only on PV charging but also AC. However, it didn't start with the version you reported, it's been around for a few months and I've always believed it's a hardware fault.

Whenever it starts charging, it keeps charging until it reaches float voltage, then switches to float mode, hence, current go down gradually. So, I had to set float voltage the same as bulk voltage.

Exactly the same.

I will check Coulomb's patched FW 60.06 .I willl see.

1 hour ago, bratpit said:

I will check Coulomb's patched FW 60.06 .I willl see.

I already tested all other suitable firmware, but the problem never disappeared. Are you able to determine when exactly your problem started?

Nope.I do not know.I bought it in early 2023.

With LFP there's no big problem when bulk=float, but the issue exist.

I mean did it start immediately after a firmware upgrade, maybe? Main, or display? Or it just started randomly?

23 hours ago, Tarek Yag said:

Is it explicitly specified that it's for VM 4 Twin? or just like all other firmware versions (model VM III Twin).

Just from the description in the original post, and the fact that it's an 84.xx that I've never seen before. I still don't know any tricks to tell a VM IV firmware from a VM III firmware.

There is a QMN (Query Model Name) and QGMN (Query General Model Name), but VM IVs only have the QMN, and return a string like "(VMIII-6000..." Sigh.

Actually, I think I may have just found a way to tell them apart: VM IVs are supposed to have an MPPT voltage range of 120-450 V, but VM IIIs have 60-450 V. But according to that, all my supposed VM IV firmwares are actually VM III firmwares! So maybe the 120 V MPPT minimum is just a documentation error 😱

On 2024/07/29 at 1:33 PM, Tarek Yag said:

Plus, a general question, is the release date hard coded into the firmware file? or it's just the file properties.

It's just file properties, sadly. And occasionally these dates get mangled; when that happens, all the files have the exact same date.

On 2024/07/29 at 1:33 PM, Tarek Yag said:

Is it the same for version 70.00 too?

Yes, unfortunatly. 70.00 has the same MPPT control code as all the other VM III / VM IV main firmwares.

 

13 hours ago, bratpit said:

Never go to bulk 55V. Go to float 54.5 and current go down gradually .

Is that premature float bug ???

It sounds like it. But you presumably have a 16S LFP battery, so 54 V is 3.375 VPC, right on the big flat part of the voltage versus SOC (with a little voltage lift due to charge current).

Does the display actually show float stage?

It could be that you're just at the flat part of the charge curve, and you run out of sunlight before the battery gets near 55 V (3.44 VPC). That would also explain why the battery voltage gradually decreases; if you have plenty of sunlight (and if the firmware will use it properly), then even in float mode, the battery voltage should not sag until nearly sunset (assuming no large loads that the battery has to supply).

If it really is going to float stage prematurely, and my patched firmware didn't prevent that, then either I screwed up the patch (though it's pretty simple), or there are other problems with these firmwares.

3 hours ago, Coulomb said:

It sounds like it. But you presumably have a 16S LFP battery, so 54 V is 3.375 VPC, right on the big flat part of the voltage versus SOC (with a little voltage lift due to charge current).

Does the display actually show float stage?

It could be that you're just at the flat part of the charge curve, and you run out of sunlight before the battery gets near 55 V (3.44 VPC). That would also explain why the battery voltage gradually decreases; if you have plenty of sunlight (and if the firmware will use it properly), then even in float mode, the battery voltage should not sag until nearly sunset (assuming no large loads that the battery has to supply).

If it really is going to float stage prematurely, and my patched firmware didn't prevent that, then either I screwed up the patch (though it's pretty simple), or there are other problems with these firmwares.

Hi thanks for response.

I've got VMIII twik 6Kw with removable display, 16SLPF. Main FW is 60.95 so unpatched by you but fans (quieter)  and MPTT are OK. If I will have time I will check it more precisely and compare it with your patched 60.06 fw.I think I was see that diode CHG was solid ON so inverter was in float stage but I am not sure.Previously  it was set bulk=float so I did not see that.

Edited July 30, 20241 yr by bratpit

21 hours ago, Tarek Yag said:

I have this exact problem but with VM IV Twin 4000 which is 24 V, but it's not only on PV charging but also AC. However, it didn't start with the version you reported, it's been around for a few months and I've always believed it's a hardware fault.

Whenever it starts charging, it keeps charging until it reaches float voltage, then switches to float mode, hence, current go down gradually. So, I had to set float voltage the same as bulk voltage, at least until I fix my BMS firmware bug, to make a successful connection between my BMS and inverter. Although it took too long, but my settings are safe for my own setup.

hello 

i have vm iii 4kw 

what is the bulk charge and float charge i can set for this bug 

 

On 2024/07/28 at 2:08 AM, Nabeel Raza said:

Can you please guide that in version 39.26 setting No 41 and 42 have appeared in inverter setting but it is not mentioned in the inverter manual what are setting No 41 and 42?

Setting 42 is associated with the first value returned by the undocumented QMBL command. Q definitely stands for Query, but I have no real idea what MBL might stand for. In setting 41, M stood for Maximum and was battery related. So maybe this is something like Query Maximum Battery Load? But setting 41 is already about maximum battery discharge current (or that's my guess from the associated QMDCHGCR, which I guessed stands for Query Maximum DisCHarGe CuRrent.

Actually, the Ms might stand for Multiple rather than Maximum. QMCHGCR and QMUCHGCR return multiple values, although these values are valid maximum charge currents (total and utility only respectively) from which to choose. The QMDCHGCR command does seem to return a list of valid values as well.

However, QMLB returns two values, the second of which has a sign (+ or -). Both are two decimal digits, apart from that sign character.

LB might stand for Lithium Battery.

Anyone care to make a different guess?

19 hours ago, Coulomb said:

Does the display actually show float stage?

It does in my case, I don't know if @bratpit has the same, actually yesterday I was sitting beside my inverter and watching it. It came to my attention that it switches to float mode (on screen too) as soon as it reaches 27.2, although my battery type is "USER" and float voltage is set to 28 just like bulk voltage.

This issue with ALL its symptoms started right after I unsuccessfully tried to connect my inverter to my BMS a couple of months ago (using "LIB" battery type) when I bought my brand new LFP battery. So, my guess is that it's related to some calibration error or something like that, which is out of my knowledge so far. However, I'm hoping to get it fixed as soon as I fix my BMS upgrade issue, which for my bad luck, is a global issue for some specific relatively new JK BMS units.

@bratpit, could you relate to the previous timing of the issue?

19 hours ago, Coulomb said:

It could be that you're just at the flat part of the charge curve, and you run out of sunlight before the battery gets near 55 V (3.44 VPC).

It happens even when charging on AC only, so it's unrelated to PV charging, or PV and AC.

19 hours ago, Coulomb said:

If it really is going to float stage prematurely, and my patched firmware didn't prevent that

Your patch was working perfectly when I used it over the course of a few months, but now it shows the same issue, so it's not about a specific firmware version.

9 hours ago, mhd_murad said:

what is the bulk charge and float charge i can set for this bug

It completely depends on your battery's type and the specifications on it. There are no general settings for all, even for the same type of battery.

8 hours ago, Coulomb said:

Anyone care to make a different guess?

Great analysis! I will try my best to give any feedback, if possible, as soon as I try DSP 84.00 with MCU 39.26. I'm having some limits in time and I can't cut off power these days at home to perform a DSP firmware update with current soaring weather temperatures (40+ degrees Celsius).

5 hours ago, Tarek Yag said:

 

@bratpit, could you relate to the previous timing of the issue?

 

I do not know what you mean?

 

 

On 2024/07/30 at 6:00 AM, Coulomb said:

 

Does the display actually show float stage?

 

This is weired. 

diode CHG is solid ON so inverter was in float stage when charging .

Yesterday at the evening  when battery discharged from 100% to 69% I switch to USB(utility) to charge  it from grid to see if it goes to bulk. Diode stayed solid on.(float). 

Today in the morning(no sun) when battery discharged to 47% I switch to grid again. Diode blinking (bulk).

Next I switch 2 more times from USB to SBU and again USB .For the first time switch to bulk (succes) but for the second time diode  went solid ON (float permanently)  .Can not go to bulk after 3 next attempts.

 

Inwerter working in USE mode.BMS is not connected to inwerter. 

 

Edited July 31, 20241 yr by bratpit

6 hours ago, Tarek Yag said:

It came to my attention that it switches to float mode (on screen too) as soon as it reaches 27.2, although my battery type is "USER" and float voltage is set to 28 just like bulk voltage.

Ok, that sounds like a completely different fault.

I was looking at the code recently, and noticed a comment I made months ago and forgot all about. The behaviour I'm used to is that the threshold current for going to float stage is one fifth of the maximum charge current setting. The logic seems to be that this setting is a very rough proxy for the battery size: larger batteries, requiring larger threshold currents, will usually have larger values for this setting. They divide this value by 5 and use that for the threshold, with 2 A as a minimum threshold. Weber and I modify this divisor from 5 to 12 for LFP flavoured fully patched firmwares; LFP has way less wasted current, and needs the lower threshold to fully charge the battery.

But in these VM III/IV firmwares, they heroically calculate a different threshold for whether you are charging from solar, from AC, or from both! As if your battery size changes depending on how you charge it. Worse, there is an EEPROM value for maximum solar current, that apparently has no setting or command to change it. And this value is 60 A for all models, even the 1500 W model (which these firmwares won't ever select). So in effect, if you are charging from solar only, the threshold is 60/5 = 12 A, from AC it's whatever you have set the AC limit to divided by 5. With both sources charging, the limit could be as high as 120/5 = 24 A! But if you have set the AC charge limit to 2A, it would be 62/5 = 12 A (truncating division (round towards zero) is used). 12 A is a little high for LFP, meaning it will usually go to float a little before the battery is fully charged.

The obvious answer is that they should make the threshold current a setting, but they seem to have resisted that over the years. Besides having umpteen settings for the RGB light pattern, etc!

I thought I'd document that while I think of it, as something to keep in mind when trying to figure out why it does what it does. But I note that this doesn't explain the observed behaviour of going to float at a fixed voltage, regardless of both float and bulk voltage settings.

26 minutes ago, bratpit said:

diode CHG is solid ON so inverter was in float stage when charging .

Ah! It was in float all along. There are some dubious lead-acid-thinking thresholds for what stage to start charging in. That's possibly one problem. [ Edit: And also how hard it is to force from one state to another as well, e.g. when to go back to bulk stage when presently in float stage. ]

I'm nearly finished patching 60.95, but I think I'll hold off and see if I can't find and fix some of these gross charging bugs first. I assume that everyone interested in the patched 60.95 will be using an LFP battery? I suppose I could make LFP and non-LFP flavoured patched firmwares. Perhaps with some more automation.

Edited July 31, 20241 yr by Coulomb

2 hours ago, Coulomb said:

I think I'll hold off and see if I can't find and fix some of these gross charging bugs first.

Yikes! This code is bad. There are multiple variables that only ever take on one value, yet are compared with several constant values.

I have found a path where the stage is set to bulk, but also the flag to immediately exit absorb stage is set. So that means that IF it enters bulk stage via this path and nothing else clears that flag, it will never stay in the absorb stage, i.e. when it exits bulk stage, it will go straight to float, not stay in absorb until conditions are right. But there is at least one other path to get to bulk stage.

There are six places in the charge control function that calls the function to check how many 12 V modules are present (i.e. is the battery 12V, 24V, or 48V?). Each of these adds or subtracts a fixed amount from the battery voltage to compare with some other value. Very likely, each of these is assuming a lead acid battery.

So it will take me a fair while to sort out the mess. The control flow (if/then/else with ands and ors and many global flags) is very complex, and of course several paths are dead because of the variables that never change value. Once I know what's actually there, I'll try to guess what is meant to be there, and finally what should actually be there.

On 2024/07/31 at 8:19 AM, bratpit said:

I do not know what you mean?

I meant did you do any similar settings change before the float issue started in your own inverter?

On 2024/07/31 at 2:16 AM, Tarek Yag said:

This issue with ALL its symptoms started right after I unsuccessfully tried to connect my inverter to my BMS a couple of months ago (using "LIB" battery type) when I bought my brand new LFP battery.

Edited August 2, 20241 yr by Tarek Yag

Only upgrade fw from 56.00 and 25.03-MCU.
I have not noticed but I wasn't looking carefully from the beginning. Pity.

I've been seeing this since I installed solar assistant.

I Changed battery type too  LIB ,PYL but without connection to BMS  I got  E61 or so and stayed with USE.

Edited August 1, 20241 yr by bratpit

@bratpit, this is the exact same thing that happened to me. I wasn't paying much attention to charging stages after both firmware upgrades (DSP and MCU), but I'm still confident that upgrading is not the reason behind the issue we're experiencing.

I started paying much attention after I failed connecting my BMS (with error 61 too); because I had to carefully set manual settings for the charger, and monitor the inverter for a while to make sure charging is safe according to my battery specifications.

I'm very suspicious about the BMS connection process, as this particular issue started after it, most probably! Especially there were random messages between my inverter and battery that caused BMS's LCD display go crazy and switch display tabs repetitively and randomly, and it even messed up charging settings back then (eg. it changed max charging current to 2A).

Ah, I'm really tired of debugging a lot of issues here at home, my highest priority right now is to fix the BMS firmware, then I'll have to do a thorough hardware repair for my inverter before any more debugging!!!

Mine is stable , apart from that but it's not big issue for LFP battery . Float is lead-acid world not LFP IMHO.

In my case 61 eroor or warning was about not connected battery to inverter .

I do not think it caused this issue but who knows.

21 hours ago, Tarek Yag said:

Especially there were random messages between my inverter and battery that caused BMS's LCD display go crazy and switch display tabs repetitively and randomly, and it even messed up charging settings back then (eg. it changed max charging current to 2A).

That sounds like you connected the BMS to the computer (RS-232) port instead of the BMS (RS-485/CAN) port. Or the two serial paths merged due to some hardware fault in the display.

There are supposed to be CRC checks on commands, but I suspect that sometimes they're not checked, or not checked properly. Interpreting BMS packets as commands, and ignoring CRCs, would explain the behaviour that you saw.