FoxESS Community - Owners & Installers Forum

Hi, I have a 6kW PV system with a Solis Single Phase Hybrid - RHI-5K-48ES-5G Inverter and 4 x Fox LV5200 batteries. The system generally works fine but over the last few weeks of very sunny weather when the batteries become fully charged in the middle of the day I am getting an Inverter 2015 BMS Alarm with the underlying Code HighVolt.BMS(33293). The alarm generally persists for about 30-45 minutes then clears itself with no apparent effect on the system operation which still seems to operate as advertised and at this point has generally started exporting to the grid.

As there appears to be no impact on operation, I am trying to establish if this is something spurious or a configuration issue. I have contacted Solis who have remotely updated the Inverter firmware and adjusted my inverter settings ( I don't know what they adjusted) but the Alarm still persists and they have advised me to contact Fox to upgrade the battery firmware.

I have 2 questions really, does anyone have any experience of this issue and/or how to resolve it and also is it actually possible to upgrade the battery/BMS firmware on the LV5200?

Thanks in advance for any thoughts or assistance,

Regards

Dave

Hello, just wondering if you had any success with resolving your alarms - I’ve been getting similar ones (BMS2015 & 1051 OV-Vbatt-H). I only have two batteries?

Hello,

I just have a 5Kw statem with 1 LV5200 battery and a Solis S5-EH1P(3-6)K-L Inverter and have the same issue when it reaches 100% charged.

HighVolt.BMS(33293)

Thanks,

Philip

Good Afternoon,

I have been searching regarding this problem for a few weeks with no solution found!
We had the system installed about 6 months ago with a Solis 3kw inverter and single Fox Ess LV5200 battery. Everything worked spot on from day one, however when the weather was really bright the battery charged to full in no time and then we were exporting to the grid at 4 pence per kWh so decided a second battery would be a good investment. Battery purchased from a reputable company (not the original installer as their price was nearly £3k plus installation) and installed as per Fox instructions including setting dip switches etc. We now have the problem you have stated, when both the batteries get to around 98 to 100% charged we get the “high volt.bms (33293)” error warning by email and the fault light illuminates on the Solis, it does “restore” itself within 20 minutes but it is very, very annoying as nobody seems to know what is causing it and how to resolve it, any suggestions would be appreciated?

hi all .
we have the same problem, the answer is that fox have new firmware for the battery and will be doing the upgrade soon.
so get on to your instaler to do the update.

Hi Everyone,

Has anyone an update on the HighVolt.BMS issue, I contacted FoxESS via their service email address last week and outlined the problem we are all having, I asked them to acknowledge receipt of my email so I was aware they had received it and would ultimately reply, to date I have not received an acknowledgment!
This is extremely frustrating!
One thing, I was in my garage where the batteries and inverter are sited and noticed the charge to be 98%, so I logged onto the Information Page and watched, at 98% SoC the Solis showed High Voltage but hadn’t yet alarmed, at 99% it went into alarm and I noted the battery voltage “spiked” at 56.5 volts for only a few seconds then it started to drop. I immediately checked the BMS Information page and noticed the FOX battery voltage at 55.1 volts, anyone any ideas because these voltages are supposed to be within the working range of the LS5200?

Hi All,

I have the 6KW version of the OP's Solis inverter and 5 x LV5200 batteries. When I had 3, then 4 batteries I always used to get the High Volt alarm when they reached 100% SOC. When I added the 5th battery I had issues where the battery did not appear to be charging and was showing very odd LED status on the battery compared to the original 4. I contacted Fox and raised a ticket. They said it was most likely a firmware mismatch between my original batteries and the new one; they sent an engineer (within a few days!). The engineer updated the firmware on all the batteries to the latest (don't know the versions that existed before the update or the number of the latest that was applied). After this, the LED status on all 5 batteries match and all is good. I have also noticed that since this update, I no longer get the High Volt BMS alarm.

Regards, Jerry

Hi everybody

I experience about the same problems as almost everyone here. Since October last year, I have 23 solar panels, no problem with those. Normally a Solis inverter of 8 kW should be installed, but that one was not available. So the company asked me if an inverter of 5 Kw together with an Solis inverter of 3 kW would be ok ? I said yes, the one with 5 kW is connected to the two Foxess LV5200; the 3 KW is only connected to the net and some solar panels. Rather fast, the same problem arose : BMS alarm when batteries reached 100 % ....... The company even replaced the two batteries, because Solis company said it was not their inverter. Result : same problem with even two new batteries. The last few days there was a lot of sun and my solar panels face almost all straight the south direction, so around midday, the light intensity is very high. At that moment, the batteries are mostly fully charged. Over the last 8 days, there were 2 or 3 BMS alarms every day. I personally think the Solis inverter can't cope, at least not with the 'normal' settings. Who can provide us, poor customers, with the right settings ???

jerryhawkins wrote: ↑Tue Sep 12, 2023 4:13 pm Hi All,

I have the 6KW version of the OP's Solis inverter and 5 x LV5200 batteries. When I had 3, then 4 batteries I always used to get the High Volt alarm when they reached 100% SOC. When I added the 5th battery I had issues where the battery did not appear to be charging and was showing very odd LED status on the battery compared to the original 4. I contacted Fox and raised a ticket. They said it was most likely a firmware mismatch between my original batteries and the new one; they sent an engineer (within a few days!). The engineer updated the firmware on all the batteries to the latest (don't know the versions that existed before the update or the number of the latest that was applied). After this, the LED status on all 5 batteries match and all is good. I have also noticed that since this update, I no longer get the High Volt BMS alarm.

Regards, Jerry

Hi Jerry,
Quite interesting. I recently added a third LV5200 battery to the system. I installed it myself, no big deal. I presume I did everything the right way, but the last battery also has odd LED status. When charging, it behaves rather normal. When fully charged, it stays that way, while the other two are discharging and have for instance 3 LEDs. Also a firmware mismatch ?
I'm sure the new battery works, yesterday a total discharge of 13 kW and today a total charge of 13 kW (according to my Soliscloud app) these figures are not possible with two batteries of this type.
So when you raise a ticket with Fox, they send an engineer, also in Belgium ?

Hi

I also have been reading in another forum, that it could help to lower the 'Floating Charge' in the control parameter settings. I lowered the floating charge to 51,0V, but still two alarms today.
In the contral parameters of the Solis inverter there is also a 'Battery Overvoltage' of 60,0V and a 'Battery Undervoltage' of 42,0V. The battery on the other hand, has a voltage range from 43,2 to 57,6V. I'm not an expert, but maybe changing the battery overvoltage and undervoltage could be the trick ????

Regards, Leiomerus

Hi Leiomerus,

Your LED symptoms seem to match mine, certainly looks like a firmware mismatch between batteries. My 5th battery would show just one LED when the rest showed 4 or 5, then would suddenly jump to all LEDs on. They would remain on whilst discharging when the other battery LEDs would go off in turn, then the 5th battery LEDs would suddenly all go out. I would think that FOX would have engineers in Belgium; all you can do is raise a ticket and see what happens. I was really impressed with their support in the UK.

Hi Jerry
I had some time today to raise a ticket with Foxess. I hope they will respond. Anyway, thanks for the advice !
Regards
Leiomerus

Hi Again,

As I didn’t get any response to my original email I did a further bit of digging and found the specific address for the U.K. service department, I then emailed service.uk@fox-ess.com and the following day got a very courteous response from Wayne. He acknowledged that they were aware of issues with some multi battery systems and advised a firmware update usually solves the problem. He requested I email him some information like battery serial numbers, error screenshot and my address. Once I had done this he immediately responded to set up a visit to my home to carry out the update, as I am away on holiday at his first suggested date the update won’t be done for another 3 weeks but I can’t fault his response to my problem!
If you are still having problems I would suggest you email the above address.

Regards

Hi everyone
The company that installed my batteries and the Solis inverter requested Solis to update the Solis inverter. Solis did that and now the BMS alarms are completely gone. I hope it will stay like this.

Regards
Leiomerus

Hi, after my original post and no responses for a few weeks I gave up checking this forum and haven't received any notifications of the numerous responses made, so apologies for not responding sooner.

Anyway, after my original post I contacted Fox and received a visit to my home where the battery firmware was upgraded and since then the error has not recurred.

I notice reading the other comments on here about the mismatch in battery LED status, I too experienced the same issue before the firmware upgrade. My original installation was 2 x LV5200 batteries and I bought and installed 2 additional units to take me to 20kW and had the mismatch between the original batteries and the newer ones. Again, the firmware upgrade seems to have resolved this and all has worked fine since.

I now have a fully working system with no issues and all is good expect for one thing - at the time of writing, 2 days away from the shortest day in December there is no sun! So my PV output which was around 36kWh on a good summers day is around 1-2 kWh per day currently. I'm looking forward to the days drawing out again....

In summary with regard to the original BMS issue, if anyone is encountering the problem I would suggest a firmware upgrade to both inverter and batteries. This can be achieved via a call to Solis and/or a support ticket and they can remotely update your inverter firmware (although make sure your wifi router is not a circuit solely powered by your inverter as when the inverter reboots so the wifi goes down and the inverter firmware upgrade fails as I found out!) Secondly a call/support ticket to Fox will allow a site visit to upgrade the battery firmware and all should be good.

As an aside, I believe that the Fox ESS LV5200 is no longer available in the UK so I guess this problem will slowly disappear as existing installations are fixed.

Dave

hi, are you based in the uk? if yes how did you manage to get fox to come out?