There is still a problem with the MPPT Can SmartSolar firmware 3.18

[ThomasManthey]

A year ago, I noticed that the solar controllers no longer functioned correctly after updating to the latest firmware.

Now, since I added a battery to my system, I also updated the firmware for the solar controllers to V3.16.

Then only one of the 7 SmartSolar controllers connected via Can was still working. Finally, I updated the GX device in my MultiGx to the latest version (3.51). Unfortunately without success. The behaviour remains the same.

Unfortunately, my account has also been deleted in the meantime and I had to register again.

So the only solution is the same as a year ago: downgrade to V3.13 ;-(

V3.13 yesterday, V3.16 today

Because I was already there, I tested version 3.15 straight away: It works “just as not” as version 3.16. Now I have all solar controllers running on V3.13 again and it works perfectly.

My system is now running:

Multi2GX V3.51

1x SmartSolar_MPPT_VE.Can_150_70_rev2_v3.13_A10C

2x SmartSolar_MPPT_VE.Can_250_70_rev2_v3.13_A114

4x SmartSolar_MPPT_VE.Can_250_85_rev2_v3.13_A116

@guystewart,

When can I expect a correction to the latest version so that I can also benefit from the improvements in the updates?

Until now I had assumed that the VictronComunity was supposed to be a knowledge base for all Victron users and therefore wrote the questions and problems in English.

However, with the changeover to the “new” system, my account has now been deleted and with it all chat histories. This means that I can no longer understand how to solve a problem myself, even if I have had it before.

Is it possible to get the chat as an export? There were a lot of interesting topics there that I would like to access if necessary.

Thanks for your help!

[guystewart (Guy Stewart (Victron Community Manager))]

Hi @ThomasManthey,

All the older community content is archived here - https://communityarchive.victronenergy.com

Unfortunately the built in search is no longer working, but it has all been crawled by google, so you can find your original topics clicking here.

This was a once off, I expect it to never happen again. Apologies for the inconvenience.

[ThomasManthey]

Hi, @guystewart,

Thank you for your quick reply. Interestingly, Google does not find all the posts I have written, even with my name. However, I have searched for the content and have already found almost all of them. I had hoped that Victron would have recognised the potential of such a forum and not just have the costs in mind ;-(

It still lacks a sensible categorisation and a useful search function.

Now I will create a personal backup of the forum with “wget” just in case.

But what about the actual reason for my contribution?

Since my post of 20 May 2024 “Is there a problem with the firmware “SmartSolar_MPPT_VE.Can_250_70_v3.15_A109.xup” ?” nothing seems to have happened regarding the CAN problem.

Apparently there are also other problems with newer firmware: “MPPT Firmware 3.16 Issues”.

When can I expect the bugs to be fixed so that I can benefit from the latest improvements to the solar controllers again?

[BecauseRV]

@ThomasManthey , have you found a solution for this yet? I haven’t looked at these forums for a while, but from quickly searching I didn’t see any solutions or feedback on this yet.

[ThomasManthey]

Please excuse my late reply, but I was waiting for help from @guystewart. The only compromise I’m using at the moment is to use version 3.13. In my opinion, however, this cannot be a solution, but only a compromise.

[RaySun]

I have two SmartSolar 150/85 tr VE.Can rev. 2 charge controllers running 3.16, seemingly without issue.

I’m trying to compare systems, but am a bit confused by: “Now, since I added a battery to my system”. Does that imply the chargers at one point were running without connection to a battery?

[ThomasManthey]

@RaySun
No, this has nothing to do with the battery configuration!
I have just got into the practice of updating the software of the components when making system changes and carrying out maintenance work.
My system consists of 2x MultiPlus II + MultiPlus II-GX configured as a 3-phase system with 3x SmartShunt for now 3 batteries. These each consist of a series connection of 2x AccuratTraction T200 24V.
I have connected the 3 SmartShunts via galvanic USB isolators to a 4-port passive HUB on the MultiPlus II GX together with an RS485 adapter, which enables communication with the E340 energy meter.
I’m amazed that the CAN bus works for you!
In my case, the last working version is 3.13. All newer versions can only find the 1st of the 7 solar controllers on the CAN.
Which version of the GX are you running? With or without large functions?

[RaySun]

The Victron system here is comprised of chargers and network/control/monitor devices.
Cerbo -s GX with stock Victron Venus OS (the latest release.)
BMV-712
SmartSolar 150/85 VE.Can
The Cerbo -s GX defaults to VE.Can on the Can bus, as do the SmartSolars. I simply plugged them in and they worked.
I use the BMV-712 for DVCC data.

[BecauseRV]

Okay, I’m in the same boat as you by keeping with version 3.13 until hearing otherwise. I just wanted to verify there was no new information on this issue that I might have missed. Thanks for getting back to me!

[ThomasManthey]

I’ve noticed that there have been quite a few updates since version 3.13 for my SmartSolar MPPT VE.CAN. Is it worth updating to check whether the CAN issue has been resolved, or is it still the same?
Just to recap: I’m still using version 3.13 because, from version 3.16 onwards, the solar controllers connected via CAN are no longer recognised, with the exception of the first one.

[nickdb (Nick)]

This has never been an issue. If it is for you then there is something else going on.
Something so severe would affect an enormous number of people and would long since have been fixed.

Solar MPPT Charge Controller changelog:

v3.18 – 17 February 2026

Released for all models

Improvements:

- Several internal improvements to overall product reliability. The solar charger will shortly pause charging (for less than 1s) when settings are changed, and nominal operation should resume in less than 30s.

Bug fix:

• - Remove battery temperature compensation from load output voltage thresholds.
• - Fix communication issue with the VE.Bus BMS v2 and VE.Bus BMS NG which prevents the charger from going into safe mode when the BMS is removed from the system.

[ThomasManthey]

In principle, I agree with you. But we won’t get anywhere here by just saying ‘if only’, ‘would’ and ‘could’. I can’t imagine that I’m the only operator of a Victron system running multiple solar controllers on the CAN bus. It’s also possible, for example, that others aren’t updating a system that’s already working.
You can see from the chat history that others are having the same problem. I expected Victron to test the issue properly rather than just talking it away. You certainly can’t accuse me of being impatient. Now over a year has passed, and clearly nothing has happened! In another Victron chat, someone complained about Victron’s poor support. I wouldn’t call this ‘support’ anymore.

Translated with DeepL.com (free version)

[alexpescaru]

Hi @ThomasManthey

When it didn’t work, did you had the chance to look at each controller address?
Cerbo menu → Settings → Services → VE.Can port → Devices → and for each device there, look at the Network Address.
They should be different. Probably, with 3.13 now, they are.
Can you confirm?

Also on Cerbo menu → Settings → Services → VE.Can port → Network status, there should be minimal errors. Ideally none.

[nickdb (Nick)]

The main change from 3.13 was to fix a bug that affected charging for multiple chargers connected via CAN that was introduced in 3.15 and fixed in 3.16.
This only affected devices not managed via DVCC or under bms control.

There has been a lot of change with the GX as well, maybe you experienced an issue with the combination of versions? Impossible to tell from here.

There have been a lot of CAN changes in the GX software, but nothing in the subsequent charger software of 3.18 (3.17 was skipped).

[ThomasManthey]

Here’s what it looks like in version 3.13:

I’ll give the latest version a go this evening.

[ThomasManthey]

My GX is running version 3.51:

[nickdb (Nick)]

I would suggest if you would like to try this again. Update the GX (download a copy of the old version first for rollback) and then try the firmware.
Also download the old charger firmware so you can rollback there as well.

All available on the professional.victronenergy.com site.

[ThomasManthey]

Which combination of GX firmware and SolarCharger firmware should I try?

[nickdb (Nick)]

The current GX is 3.72.
There is only one firmware version above yours for the chargers - 3.18.
But update the GX first. Verify all is well,
Then do one charger.

[ThomasManthey]

OK, tonight I’m going to try out the combination of GX V3.72 and SmartSolar V3.18.
Fortunately, the GX is very reliable when it comes to software updates. It always saves the last working version. That way, if it doesn’t work, I can easily revert back.