BMS for Schneider Conext

[shorawitz]

I'm still in research mode - haven't received my batteries yet on the Slow Boat from China. Is the Orion Jr. just controlling StdBy/Online mode? If not, what functions are you able to perform? I want to try to build in a soft-start relay to the BMS. I bought a few 5 Ohm resistors to setup a minimal current path along with a SSR to control it. If you've seen "Beginning From This Morning's" YouTube channel, they did this using the REC BMS.

 

[shorawitz]

Build some for sale, I'd be interested. Schneider doesn't seem to want to let any cats out of their Xanbus bag.

Got my batteries this week...

I'm getting closer to having a solution for this. I think I'll be ditching the GWL board. They didn't want to play nicely by giving me any information for the I2C bus on their board. Too bad. It has all of the inputs I was looking for, but they want to sell their Communicator and Controller for an extra $55 plus shipping. All it does is provide a web interface to the controller board. It could work, but that's an extra board to take up power, another port of my switch (and the board only comes w/10Mb - not there would be a lot of data to pass however,) and I'd still need a Pi or Ardiuno to talk Modbus to the Schneider gear.

I did come across another option that could be used (costs a little more though.) I could get a Daly Programmable Configurable Smart BMS with UART, RS485, and CAN and connect it to a Pi or Arduino. Heck, I might even try wiring up the Daly directly to the Conext2 Gateway via RS485 and see if it can see/talk to it. In the end, Daly is a known quantity and I found videos and docs on how to use the communication on it. GWL is an unknown in the U.S. even though I think it could work and provide more features (minus BT.)

 

[SEcureenergy]

Got my batteries this week...

I'm getting closer to having a solution for this. I think I'll be ditching the GWL board. They didn't want to play nicely by giving me any information for the I2C bus on their board. Too bad. It has all of the inputs I was looking for, but they want to sell their Communicator and Controller for an extra $55 plus shipping. All it does is provide a web interface to the controller board. It could work, but that's an extra board to take up power, another port of my switch (and the board only comes w/10Mb - not there would be a lot of data to pass however,) and I'd still need a Pi or Ardiuno to talk Modbus to the Schneider gear.

I did come across another option that could be used (costs a little more though.) I could get a Daly Programmable Configurable Smart BMS with UART, RS485, and CAN and connect it to a Pi or Arduino. Heck, I might even try wiring up the Daly directly to the Conext2 Gateway via RS485 and see if it can see/talk to it. In the end, Daly is a known quantity and I found videos and docs on how to use the communication on it. GWL is an unknown in the U.S. even though I think it could work and provide more features (minus BT.)

Hi, I’m looking also for a AC coupled Inverter BMS/Balancer solution. Any news on your project?
I have (3) 48 volt 94AH lithium Ion battery packs. 4.8kw ea for a total of 14kw aprox.
I didn’t purcharsed the inverter neither BMS/balancer
Any suggestions will be very appreciated.
Best regards

 

[shorawitz]

Hi, I’m looking also for a AC coupled Inverter BMS/Balancer solution. Any news on your project?
I have (3) 48 volt 94AH lithium Ion battery packs. 4.8kw ea for a total of 14kw aprox.
I didn’t purcharsed the inverter neither BMS/balancer
Any suggestions will be very appreciated.
Best regards

Are you planning to purchase Schneider? I can't say enough about how they've stepped up to provide me service. I lost one of the PDP hinge brackets while I was installing it and they sent out a whole new unit and paid for shipping here and back. I removed the bracket from thew new unit and sent it back. I had a problem with my inverter not accepting a firmware upgrade, and they did the same thing (except I still have the old inverter - they never asked for it back.)

I'm still looking to do the DIY BMS. For the $$$, I'm not really going to use all of the features of the big commercial options. Stuart Pittaway has a project that is easily expandable (for close to the big-boy prices, I could even put a cell module on every parallel cell if I really wanted to) and can talk CAN or ModBus to the equipment.

Right now, I purchased a 2A cell balancer on eBay that monitors battery voltage and individual cell voltages as well as resistance. It has a pretty good Bluetooth app that I was attempting to hack, but it uses BLE (Bluetooth Low Energy) and there isn't a whole lot of utilities/documentation on how to connect to it from a computer - I even bought a BLE USB adapter to try to make it work. I know W.P. says not to waste your money on balancers like this, but it really does a good job of keeping my cells in balance and everyone that's posted a video on YT raves about them. You actually don't have to use the balancing feature - just use it to monitor cell health.

I also found (of course after I purchased my balancer) another balancer that can talk CAN & RS485 (ModBus.)

CAN Bus RS485 Protocol Battery Active Equalizer Balance Bluetooth 2S ~ 24S BMS | eBay

Find many great new & used options and get the best deals for CAN Bus RS485 Protocol Battery Active Equalizer Balance Bluetooth 2S ~ 24S BMS at the best online prices at eBay! Free shipping for many products!

www.ebay.com

I might pick this up and use a Raspberry Pi as it will be even cheaper and easier than the diyBMSv4 (I can use Python instead of C to program it.) I'll probably sell the current 2A balancer I have if I end up going this route. Right now, the way I have my Schneider gear setup, I'm not desperate for the BMS. I have the Schneider BattMon as well. With that in my system, and with the settings I've programmed into the CC and inverter, my cells never get above 3.4V. And with my current usage, I rarely go below 70% of capacity. Now sooner than later, I'll need the juice and I'll need to worry about the low end and that is when I'll get going on my BMS solutions.


Stuart's GitHub page that has all of the code and information:

GitHub - stuartpittaway/diyBMSv4: Version 4 of the diyBMS

Version 4 of the diyBMS. Contribute to stuartpittaway/diyBMSv4 development by creating an account on GitHub.

github.com

 

[SEcureenergy]

Are you planning to purchase Schneider? I can't say enough about how they've stepped up to provide me service. I lost one of the PDP hinge brackets while I was installing it and they sent out a whole new unit and paid for shipping here and back. I removed the bracket from thew new unit and sent it back. I had a problem with my inverter not accepting a firmware upgrade, and they did the same thing (except I still have the old inverter - they never asked for it back.)

I'm still looking to do the DIY BMS. For the $$$, I'm not really going to use all of the features of the big commercial options. Stuart Pittaway has a project that is easily expandable (for close to the big-boy prices, I could even put a cell module on every parallel cell if I really wanted to) and can talk CAN or ModBus to the equipment.

Right now, I purchased a 2A cell balancer on eBay that monitors battery voltage and individual cell voltages as well as resistance. It has a pretty good Bluetooth app that I was attempting to hack, but it uses BLE (Bluetooth Low Energy) and there isn't a whole lot of utilities/documentation on how to connect to it from a computer - I even bought a BLE USB adapter to try to make it work. I know W.P. says not to waste your money on balancers like this, but it really does a good job of keeping my cells in balance and everyone that's posted a video on YT raves about them. You actually don't have to use the balancing feature - just use it to monitor cell health.

I also found (of course after I purchased my balancer) another balancer that can talk CAN & RS485 (ModBus.)

CAN Bus RS485 Protocol Battery Active Equalizer Balance Bluetooth 2S ~ 24S BMS | eBay

Find many great new & used options and get the best deals for CAN Bus RS485 Protocol Battery Active Equalizer Balance Bluetooth 2S ~ 24S BMS at the best online prices at eBay! Free shipping for many products!

www.ebay.com

I might pick this up and use a Raspberry Pi as it will be even cheaper and easier than the diyBMSv4 (I can use Python instead of C to program it.) I'll probably sell the current 2A balancer I have if I end up going this route. Right now, the way I have my Schneider gear setup, I'm not desperate for the BMS. I have the Schneider BattMon as well. With that in my system, and with the settings I've programmed into the CC and inverter, my cells never get above 3.4V. And with my current usage, I rarely go below 70% of capacity. Now sooner than later, I'll need the juice and I'll need to worry about the low end and that is when I'll get going on my BMS solutions.


Stuart's GitHub page that has all of the code and information:

GitHub - stuartpittaway/diyBMSv4: Version 4 of the diyBMS

Version 4 of the diyBMS. Contribute to stuartpittaway/diyBMSv4 development by creating an account on GitHub.

github.com

Thanks a lot!
Yes I probably purchase a schneider and the “CAN Bus RS485 Protocol Battery Active Equalizer Balance Bluetooth 2S ~ 24S BMS” that is on ebay from seller ICGOGOGO.
One more question. I’m very newbie working with batteries. I have (3) banks of 14 li-ion 94AH for a total of 42 batteries
The 3 banks will be in parallel. Can I put just two BMS and connect 21 batts on each one? Or is better practice to just use one per bank?

 

[shorawitz]

I assume you have the 4.2V cells since you're doing 14S. It's usually best to parallel first, then series when you build your battery - make one big battery then all you need is a 14S BMS. You'll want to make sure they are all equalized. What I did with mine was to parallel all 64 cells and charged them to 3.5-ish (I have LiFePO4 chemistry) using my bench power supply (you can buy one on Amazon for not a lot of $$, just make sure you get one that can do 10A or it will take 2-3x longer to get them topped off.) Then I let them rest until the voltage settled and to make sure they balanced each other. Then I built my battery as a 4P16S (LiFePO4.) I also made my own bus bars from copper bar stock. I've attached a Sketchup drawing of how mine are setup. I used 2x8 blocking at the ends and 4 rods of all-thread to compress them. I bought some clear tubing to encase the all-thread rod into for safety. The hardest-longest part was building the bus bars. I wanted as few connections as possible to minimize voltage drop across the whole battery.

Like I said about the Schneider BattMon - I derated the Ah total for mine from 1088Ah rated down to 980Ah and (so far) I haven't seen them drop below 70% as tallied by the BattMon/Shunt. I expect these to last me at least a decade. I have my CC set to 56V Bulk, 54.6 Absorb for 45 mins (though I'm thinking of extending this - I've been extending it as I go and watching the Balancer. The cells never really get past 15mV out of balance. I have Float set to 54V. You can adjust accordingly for your chemistry.

 

[shorawitz]

I should have mentioned, you can check out how my system is setup on my YouTube channel: JC/DC in the AZ https://www.youtube.com/channel/UC8_TU2g-Yl1oMCts3pkXCbQ

I'm going to be posting a new video soon with my battery upgrade stuff. We live 100% off-grid, so lots of cool stuff going on.

 

[shorawitz]

OK gang! I finally have a working prototype for the software component. I finally figured out how to convert ModBus values to ASCII so I can view real values. I've setup a server to provide API access to (today) specific aspects of my Scheider setup over ModBusTCP. The fields I currently have access to: Name, SOC, Voltage Capacity, State, Status, Load, Faults, Warnings, PV Power, DC Power. Basically, I can get any information I want now via the Conext Gateway. I can even send commands like: switch CC to Float or put the Inverter in StdBy. I've linked my API to my installation of Home Assistant. I'm able to display all the aspects above on my HA dashboard - really cool!

If you haven't seen Home Assistant, it's pretty nice. I have a lot of my house setup to use it like lights, H2O heater, Temp sensors and now Scheider!

I've looked over a lot of different hardware for monitoring the cells. I haven't decided yet on what I want to use:
ModBus Balancer/Cell Monitor (can get these on eBay)
DIY BMS (there are few out there, but Stuart Pitaway is the leader for these)
GWL CPM board (Comes from EU, so shipping takes some time and support will lag a day or two)

I think the cheapest option is the Balancer. I have one now (2A balancer/24 cells) that is popular on YouTube, but it only does BLE and I couldn't hack this one. So I'm looking at the CAN/ModBus model. Both you can get on eBay. You don't have to turn on the Balancer, but I haven't found any adversity using it and lots of people on YT are using that way.

 

[shorawitz]

FYI: here is a screen shot of my Solar Dashboard in Home Assistant.

 

[400bird]

That is awesome news!

I need to research more and dig (after I complete the install and pass inspection), but I would be very interested to see more if you are willing to share on GitHub or something.

 

[JoeHam]

Basically, I can get any information I want now via the Conext Gateway. I can even send commands like: switch CC to Float or put the Inverter in StdBy.

You probably know this but others may not.

NEVER put the inverter in standby unless you have a ComBox externally powered. It will brick the system. The Gateway may not have this issue.

I learned this the hard way:

HELP! Schneider Conext SW and ComBox

So I got my SW 4048 up and running with my critical loads panel connected. Worked fine. Then I hooked up the ComBox and established communications with the Conext SW. While testing the communications I hit the standby tab. I now know that this immediately shuts down the entire system, which...

diysolarforum.com

 

[shorawitz]

You probably know this but others may not.

NEVER put the inverter in standby unless you have a ComBox externally powered. It will brick the system. The Gateway may not have this issue.

I learned this the hard way:

HELP! Schneider Conext SW and ComBox

So I got my SW 4048 up and running with my critical loads panel connected. Worked fine. Then I hooked up the ComBox and established communications with the Conext SW. While testing the communications I hit the standby tab. I now know that this immediately shuts down the entire system, which...

diysolarforum.com

Interesting. I wonder if this applies to also having an SCP. I just looked at my SCP and it does have an option for StdBy. Did you find any docs that say not to do this w/o a Combox or Gateway?

 

[shorawitz]

That is awesome news!

I need to research more and dig (after I complete the install and pass inspection), but I would be very interested to see more if you are willing to share on GitHub or something.

No problem. I created a video on my YT channel where I demonstrated my setup w/Home Assistant:

https://www.youtube.com/channel/UC8_TU2g-Yl1oMCts3pkXCbQ

And I did publish the code on Github. If there's interest, I could publish another video going into more details on getting this seutp.

 

[JoeHam]

Interesting. I wonder if this applies to also having an SCP. I just looked at my SCP and it does have an option for StdBy. Did you find any docs that say not to do this w/o a Combox or Gateway?

It’s somewhere in the 125 page manual which was not provided with my CSW4048 as noted in my HELP thread post mortem note.

I don’t believe this is an issue with the SCP but I don’t have one so no experience there.

 

[jtvt]

It’s somewhere in the 125 page manual which was not provided with my CSW4048 as noted in my HELP thread post mortem note.

I don’t believe this is an issue with the SCP but I don’t have one so no experience there.

With XW, you only brick your system when you perform an inverter firmware update without alternate power to the combox/gateway. IIRC the firmware readme warns about this. You should be able to put the system into standby via the combox/gateway/scp without any problem as long as you are not doing a inverter firmware update. Maybe there is something weird with the SW units.

IMO, the SW inverters are crap. Years ago I bought two of them to use synchronized. They kept frying when the generator came on. There is/was some bug that causes one inverter to feed the other in some weird current loop. As stand alone units they worked fine for me, but I've heard of other problems with single units and generator use. I went through 6 of those SW inverters working with Schneider support. They identified a bug in the inverters and tried to fix it and gave me new beta firmware, but it didn't work. After going through all those SW inverters, they eventually gave me two XW4024 units with pdp and all the stuff required for putting then in parallel. I didn't have a problem with the XWs for ~10 years until I went to replace my battery. They no longer sync, but work fine as standalones. The problem is they read different dc voltages. There is a tool to calibrate this but it's $600 and I was moving to 48v anyway. Now I have a XW6848 pro which was a drop in replacement since it works with the same pdp, etc. The XWs are solid units, SW not so much.

 

[LR~Eagle]

With XW, you only brick your system when you perform an inverter firmware update without alternate power to the combox/gateway. IIRC the firmware readme warns about this. You should be able to put the system into standby via the combox/gateway/scp without any problem as long as you are not doing a inverter firmware update. Maybe there is something weird with the SW units.

IMO, the SW inverters are crap. Years ago I bought two of them to use synchronized. They kept frying when the generator came on. There is/was some bug that causes one inverter to feed the other in some weird current loop. As stand alone units they worked fine for me, but I've heard of other problems with single units and generator use. I went through 6 of those SW inverters working with Schneider support. They identified a bug in the inverters and tried to fix it and gave me new beta firmware, but it didn't work. After going through all those SW inverters, they eventually gave me two XW4024 units with pdp and all the stuff required for putting then in parallel. I didn't have a problem with the XWs for ~10 years until I went to replace my battery. They no longer sync, but work fine as standalones. The problem is they read different dc voltages. There is a tool to calibrate this but it's $600 and I was moving to 48v anyway. Now I have a XW6848 pro which was a drop in replacement since it works with the same pdp, etc. The XWs are solid units, SW not so much.

I have the SW4048 installed in 2018 and it has been rock solid.
What year SWs did you have problems with?
They seem to have address the problems as I haven't heard of current complaints.

 

[jtvt]

I have the SW4048 installed in 2018 and it has been rock solid.
What year SWs did you have problems with?
They seem to have address the problems as I haven't heard of current complaints.

That's around 2014. I think there is something inherent with their design that is the problem. I've heard of newer ones having similar problems. Mostly in parallel, but not always.

 

[Horsefly]

Interesting. I wonder if this applies to also having an SCP. I just looked at my SCP and it does have an option for StdBy. Did you find any docs that say not to do this w/o a Combox or Gateway?

I have a CSW4024 and the SCP. No Combox or Gateway in my system. Our standard procedures are to put the Inverter in standby (via the button on the SCP) whenever someone departs from a visit to the cabin. When someone makes a new visit to the cabin, they take the inverter out of standby via the same button. This has worked fine for 4 years.

 

[shorawitz]

I've updated the API to now display the correct temperature of the batteries if you have a probe plugged into your system. It took me a while to figure out how they are calculating the value and Schneider support didn't even have the answer. I happened across it in the latest BatMon manual that has a section for Modbus and the calculation is listed there.

Here's my Github repo:

GitHub - shorawitz/conext-api: Python code to query Schneider Conext Gateway

Python code to query Schneider Conext Gateway. Contribute to shorawitz/conext-api development by creating an account on GitHub.

github.com

Here's my YouTube channel where I talk about all things solar and off-grid:

https://www.youtube.com/channel/UC8_TU2g-Yl1oMCts3pkXCbQ

Here's a new screen shot of my Home Assistant Solar dashboard. I have a temperature sensor in the room next to the inverter (bottom left graph) and a Wifi connected A/C (bottom right) show it's current temp and setting that I can adjust as needed from HA using my cell phone:

 

[Anit767]

I am looking to add a Schneider Conext XW pro for battery storage to my existing solar.

Currently I have a 6kw Solar Edge inverter.
I installed this system myself along with the 20 panels on the roof and the critical loads panel.

I suppose I am not stuck on the Schneider, but it is rated to provide enough current to start and run my AC.


The question I have, does anyone know what BMS's can communicate on the RS485 the Conext gateway provides for the battery? I can't find any that do. There is some old literature that the 48v LG resu would work. But I think that LG discontinued that battery?

Thanks in advance!

I‘m about to purchase a solaredge grid tie inverter. I’m considering getting a used Schneider hybrid CONEXT 4048. Do you know if these two inverters can be ac coupled?