SOC issues. Can I connect Cerbo GX to Solis Inverter? Need a battery monitoring system

[xKatutis]

Hello I need a little bit of an assistance.

My current setup:
3x JK BMS ( JK-PB2A16S20P ) for my 3x EV car 113 Kwh battery. (1 EV car battery = 1 BMS)
15kw Solis Inverter S6-EH3P15K02-NV-YD-L

My issue: The JK Bms's are calculating and reporting wrong SOC's on a constant matter. I realize that the JK bms isn't really meant for such massive capacity (2354.17 Ah each battery) and total system 7,062 AH capacity.
And since the master BMS reports wrong (and glitchy) SOC to the inverter, the inverter keeps on shutting down the Backup power. You can read a bit more in-depth of my BMS issues of resetting the SOC from 72% to 0% to the inverter \ o /

What I'm doing about it?
Currently I'm considering of purchasing a Victron Smart Shunt to do all of my Capacity calculations. I also realize that the Smart Shunt alone can't communicate with the Solis Inverter, so I'm also considering of getting the Victron Cerbo GX communcation hub, but what I can't find is..


Will the Cerbo GX be able to communicate and work with my Solis Inverter via the CAN BMS protocol? I honestly keep seeing conflicting information all around and I honestly don't want to purchase paper weigth.

Also instead of the Victrom Smart Shunt, maybe someone has any better suggestion to my issue? I mainly need 2 things: To know the correct SOC for myself and the Inverter to retrieve decently accurate SOC data so that I do not loose power randomly throughout the usage.

 

[Brucey]

My suggestion. Run open loop (no comms). Use smartshunt and Victron connect via BT to keep an eye on things. Set Solis to use voltage instead of bms comms. So it will only shutoff at 48V for example. There's no way a single jk bms can track a 113kWh battery.

There is a battery size limit of 9999Ah in the smartshunt but you are below that.

 

[xKatutis]

My suggestion. Run open loop (no comms). Use smartshunt and Victron connect via BT to keep an eye on things. Set Solis to use voltage instead of bms comms. So it will only shutoff at 48V for example. There's no way a single jk bms can track a 113kWh battery.

There is a battery size limit of 9999Ah in the smartshunt but you are below that.

View attachment 285842

Current issue is that Solis Inverter does not allow me to set the voltages required for my Batteries. As it's a S14 massive battery unlike normal S15 - S16th.

Which is the reason why I'm rather unable to run it on Open loop without comms to the Inverter. Inverter sees no battery = no use any battery -_-' It's horrible

 

[MattMan119]

If you have not calibrated the volts and amperage within the JKBMS is will be very very wrong SOC.. I did this and it helps a lot .. like now days and days I will be 1% off, prior to calibration I could be off as much 5-8% in a only a few days.. (it's not perfect but very close to the Victron smart shunt that I use to compare to)

 

[ricardocello]

According to this, the inverter supports a long list of standard batteries, which you do not have.

https://www.solisinverters.com/uploads/file/Solis_Leaflet_Battery_matching_S6-EH3P(8-15)K02-NV-YD-L_V1,2_202503.pdf

It says to use “Lithium Battery” if not in the list.
Presumably, this assumes 16s so it isn’t working.
How did you configure it to use the JK?

Perhaps one possibility is to write custom software on a raspPi with a CANhat to emulate one of the supported batteries, and gather the relevant info from the SmartShunt. But that is major DIY hardware/software work. You would have total control over the SoC going to the Solis.

Cerbo GX with CAN will not help you talk to the Solis. Victron does not talk to other inverters.

 

[kommando]

Upgrade to firmware 15.38 on the JK, this has a software fudge to cover the JK internals chips issues at very low currents, before 15.35 a small current showed as 1A regardless of the actual A being say 100mA. With a very low overnight A I was losing way more SOC % than expected. The new firmware overcomes this by changing the flow direction intermittently, still not accurate but no more drift overnight for me.

 

[xKatutis]

According to this, the inverter supports a long list of standard batteries, which you do not have.

https://www.solisinverters.com/uploads/file/Solis_Leaflet_Battery_matching_S6-EH3P(8-15)K02-NV-YD-L_V1,2_202503.pdf

It says to use “Lithium Battery” if not in the list.
Presumably, this assumes 16s so it isn’t working.
How did you configure it to use the JK?

Perhaps one possibility is to write custom software on a raspPi with a CANhat to emulate one of the supported batteries, and gather the relevant info from the SmartShunt. But that is major DIY hardware/software work. You would have total control over the SoC going to the Solis.

Cerbo GX with CAN will not help you talk to the Solis. Victron does not talk to other inverters.

Thank you very much for the list!
It does assume that the Lithium battery is 16s. JK BMs allows me to configure to be 14s Lifepo4 batteries. Max capacity is the main issue which allows me to set at max 2000ah, which means the SOC is all over the place.

Anyways on Solis inverter it does allow me to set lower voltages that would actually work for my batteries, except that it randomly without reason resets back to defaults \ o / And nothing I do with the Solis inverter can remedy that for whatever the reason is :/

"Cerbo GX with CAN will not help you talk to the Solis. Victron does not talk to other inverters."
damn..

Perhaps one possibility is to write custom software on a raspPi with a CANhat to emulate one of the supported batteries, and gather the relevant info from the SmartShunt. But that is major DIY hardware/software work. You would have total control over the SoC going to the Solis.

It seems like it. I'm currently looking at ESP32 module builds, that would do the job but ehhh...

I wonder if I have any other options

 

[xKatutis]

Upgrade to firmware 15.38 on the JK, this has a software fudge to cover the JK internals chips issues at very low currents, before 15.35 a small current showed as 1A regardless of the actual A being say 100mA. With a very low overnight A I was losing way more SOC % than expected. The new firmware overcomes this by changing the flow direction intermittently, still not accurate but no more drift overnight for me.

All 3 bms are at 15.38 version, unfortunately due to not being able to set the correct Capacity, the SOC keeps falling down hard in one way or the other. JK support has never replied to me for past 2 months

 

[SeaGal]

Anyways on Solis inverter it does allow me to set lower voltages that would actually work for my batteries, except that it randomly without reason resets back to defaults \ o / And nothing I do with the Solis inverter can remedy that for whatever the reason is :/

I'm not familiar with the "S6-EH3P15K02-NV-YD-L" - presumably that is a 3 phase version. I have two S5 Solis inverters with custom DIY battery to Solis CAN comms, running on an ESP32 with some of the CAN side of the code derived from @sijones2010's project (see link below).

The Solis supports a few common protocols over CAN such as Pylontech and plain vanilla SMA.

The BMS's request for charge voltage will override any setting you set on the Solis itself, but with comms running, you can specify charge voltage and current to your heart's content

"Cerbo GX with CAN will not help you talk to the Solis. Victron does not talk to other inverters."
damn.

It seems like it. I'm currently looking at ESP32 module builds, that would do the job but ehhh...

I wonder if I have any other options

Take a look at this project...

Thread 'DIY Battery via Smart shunt to inverter integration (Solis etc)'

Aug 6, 2022

Hi All,

I've taken some code that handles Victron's VE.Direct protocol (Smart Shunt) and added in CAN Bus / PylonTech protocol connections, this allows the State of Charge, Voltage, Amps etc all be sent to the inverter - any one that supports the PylonTech protocol.

The Victron implementation code is now Victron's own, this solution has been rewritten and is being improved on all the time.

I have it connected to a Solis and works perfectly.

Secondly as it has MQTT I implemented commands that can be sent to enable and disable charging, and force charging, this I did so if solar...

• sijones2010
• Replies: 339
• Forum: DIY Solar General Discussion

• 

 

[xKatutis]

I'm not familiar with the "S6-EH3P15K02-NV-YD-L" - presumably that is a 3 phase version. I have two S5 Solis inverters with custom DIY battery to Solis CAN comms, running on an ESP32 with some of the CAN side of the code derived from @sijones2010's project (see link below).

The Solis supports a few common protocols over CAN such as Pylontech and plain vanilla SMA.

The BMS's request for charge voltage will override any setting you set on the Solis itself, but with comms running, you can specify charge voltage and current to your heart's content



Take a look at this project...

Thread 'DIY Battery via Smart shunt to inverter integration (Solis etc)'

Aug 6, 2022

Hi All,

I've taken some code that handles Victron's VE.Direct protocol (Smart Shunt) and added in CAN Bus / PylonTech protocol connections, this allows the State of Charge, Voltage, Amps etc all be sent to the inverter - any one that supports the PylonTech protocol.

The Victron implementation code is now Victron's own, this solution has been rewritten and is being improved on all the time.

I have it connected to a Solis and works perfectly.

Secondly as it has MQTT I implemented commands that can be sent to enable and disable charging, and force charging, this I did so if solar...

• sijones2010
• Replies: 339
• Forum: DIY Solar General Discussion

• 

Yup already have found this project today, and I've already managed to purchase the Smart shunt. I'll try to integrate that whole DIY project, though I'm bit confused on the ESP32 parts, I will be looking at tutorials on how it works and how to setup for sure..

Do you perhaps have any pointers you could tell me about it? What to buy or what to avoid?

 

[SeaGal]

Feel free to ask anything specific, but best on that other thread - as I see you have already posted to.