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JBD/Overkill BMS CAN bus comms support for inverters

uksa007

Solar Enthusiast
Joined
May 26, 2022
Messages
239
Hi,

Updade: Support now available for JBD/Overkill BMS CAN bus comms for inverters similar to my JK-BMS CAN bus project.
This would also facilitate integration with Home Assistant and control of the battery/inverter remotely see my JK-BMS CAN comms for example:

My Hardware interface now supports the JBD/Overkill BMS.
Let me know when ordering you require the JBD/Overkill version.
Update: Multi BMS support up to 10 BMS also available, kit available.

This has all the hardware/software needed to communicate with BMS and Inverter over CAN bus.
Hand built on a PCB and soldered to the ESP32, bulletproof design for production use.
Don't use modules and Dupont connectors for long term production use, they are for proof of concept and prototyping only, and are prone to fail.

It is a plug and play device, just add power (5v USB)
Now available with two RJ45 with Termination disabled for Multi BMS use.

This will allow your JBD/Overkill BMS to communicate with any inverters that support Goodwe and Pylontech Low voltage batteries via CAN bus (Protocol compatible with Pylontech V1.3 and Goodwe V1.5), this should be most 48V inverters, hybrids etc.

Thought this may help some others who would like inverter comms with their JBD/Overkill BMS.
This enables the following:

Sends over CAN bus to inverter:
  • Battery Voltage
  • Battery Current (+charge, -discharge)
  • State of Charge (SOC)
  • State of health (SOH)
  • BMS Temperature
  • Charging Voltage
  • Charging Amps
  • Discharge min Voltage
  • Battery name
  • Alarms: Cell over/under voltage, Charge/discharge over current, High/low Temp, BMS fault
  • Charging logic: Complete rework of the charging logic, now charges with constant current(CC) to the absorption voltage, then has an absorption timer (Constant Voltage, user configurable time), with rebulk feature (user configurable offset from absorption voltage).
Note:- Support for only one BMS CAN connection per inverter, see here more info on creating larger capacity packs
Early stages are under way to support multiple BMS, but need funding to purchase additional hardware, please consider supporting my work if you would like to see this functionally, early access code with be made available in the Alpha testers membership once funding goals are reached:


Home Assistant native integration via ESPHome:
  • Battery control switches to manage battery remotely
    • Charging request status
    • Absorption voltage (slider)
    • Charging current max (slider)
    • Charging enabled/disabled
    • Discharging enabled/disabled
    • Charging manually (top balancing)
  • All BMS sensor values
123038


I'm using it in my production environment which consists of:
  • Goodwe GW5000S-BP 5kW inverter
  • Goodwe GM3000 3 phase Smart meter cabled back to inverter (you can also use the GM1000 if you have single phase)
  • 16 * EVE LF280K batteries in series for nominal 51.2v
  • JK-BMS 150A model JK-B2A24S15P
  • JK RS485 module (you don't need this if your ESP32 is near the JK-BMS)
  • ESP32 model esp32doit-devkit-v1
  • TJA1050 CAN bus to TTL module 4.7K resistor for 5V to 3.3v level shift.
  • RS485 to TTL module (you don't need this if your ESP32 is near the JK-BMS)
  • Various safety devices: Fuse and ZJ Beny125A DC circuit breaker etc.
Additional info will be published to "Be in the know" and above like:

What development is coming soon
Development that has been completed and is in Alpha/Beta testing
Get early access to Alpha/Beta code for testing (in those tiers)
Polls to determine future features etc.
Help fund goals to purchase additional hardware like multiple BMS support

Thanks.
 
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For Victron, there's already something going:


 
Yes, would it support multiple Overkill BMSs in parallel?
Initially it will be single BMS per inverter with Home Assistant integration, you have to walk before you run!
Once the Multi BMS goal is reached it will enable me to purchase another set of batteries/hardware to finish development, test and release Multi BMS support.
If you want this feature I suggest you consider the Alpha tester membership, as this is where early access will be made available, once the hardware goal is reached.

PS work has begun on it, it's a fairly major rewrite that will require significant testing hence the need for additional hardware.
# V2.00 Multi BMS support
Send CAN direct from lambda, enables Master/multiple slave BMS support
 
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What size pins / terminals fit the jbd port?
(I don't know the proper terminology, yet.)
The ones I bought from overkill are to wide and spaced to far apart to fit my jbds so I need to cut the ends off and put the correct on.
 
My project would enable JBD/Overkill BMS CAN comms with all inverters that support the Pylon/Goodwe LV protocol, which would be almost all LV battery/hybrid inverters, not just Victron.

This is great will it work with voltronics as well?
 
This is great will it work with voltronics as well?

That's not one I'm familiar with, what model?

What does the manual say for supported batteries, does it mention CAN bus and pylon?
 
Sorry probably a really dumb question but I'm really new to this. How do I know if my BMS board has a can bus? I have a 30s 40a jbd bms. I want to communicate via CAN to the evcc 3.0
 
Sorry probably a really dumb question but I'm really new to this. How do I know if my BMS board has a can bus? I have a 30s 40a jbd bms. I want to communicate via CAN to the evcc 3.0
Hi,
So you don't need CAN bus on the BMS, even if you had it, it would probably be in the wrong format.
You need a UART connection, usually used for the Bluetooth or similar, my code and hardware produce the CAN data for the inverter.
However it is only for Low voltage application eg 48,v.
High voltage inverters use a different protocol.

What voltage and how many cells are you running?
You need to check you inverter manual and see what CAN protocols/batteries types it supports.

Edit: Quick check and it seems the evcc 3.0 is some kind of EV charger?
My project is for use with home storage inverters, EV charges are a different world.

To answer your question, you need to look in the manual for the BMS to see if it has a CAN port.
But as I said that does not mean it is using the correct protocol to communicate with your evcc, you would need to ask the BMS manufacturer what CAN protocol it is using.
 
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Cool project, I was thinking about doing something very similar to this.

A couple additional features that should be fairly simple to integrate would be to activate an external active balancer and to have a setable heat function. To turn a heat pad on, to keep the pack from freezing.

Also the voltronic inverters only support pylontech protocol over rs485, so that would also be a nice function to see.
 
A couple additional features that should be fairly simple to integrate would be to activate an external active balancer and to have a setable heat function. To turn a heat pad on, to keep the pack from freezing.

Also the voltronic inverters only support pylontech protocol over rs485, so that would also be a nice function to see
Paterons have a chance to vote on future features, please consider supporting my work and have input into future features, link in the first post.
 
Update on Overkill/JBD support:

The nice guys over at Overkill solar are sending me a BMS to test with.
I have already finished the ALPHA code which is working, just waiting on the BMS to arrive start testing.
Have made a prototype hardware interface that will essentially make it plug and play for most inverters.
Hardware interface will be available to purchase for Patrons.
 
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Hardware interface prototype has be assembled and is in testing.
Hardware interface has support for Overkill/JBD and code is in full testing using a JBD-SP25S003-L16S-100A

1678975836506.png
 
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Thanks for your work on this. I'm a long way from considering implementation as I just got my 16S system up and running with a 200A JBD, but I'm running a Sol-Ark 15k and am HomeAssistant-curious. Once I get my second 16S pack going, I'll subscribe to your patreon and try to get comm's working with your product.

Until then, I ordered an (untested, presumed good) 5 pack of JBD SP25S003 LifePo4 100A BMS's from Current Connected a while back in their sale. I sold 2, and I probably only need 2 of them myself. So if your development gets to the point where you need another JBD of this make/model, let me know and I'll send you one at my cost. Can give you more details on the module if you want to shoot me a DM.
 
If I'm not having a blonde moment, it would appear that you are promoting a commercial offering, albeit thinly disguised as a plea for money for development. It appears that you are aiming to get over $3000 to buy new batteries and BMS, via your patreon link?

As far as I can see, none of the code you are promoting on here is available free of charge. Yet, what you are aiming to do is largely covered by existing free github projects.

I'm not an Admin on here, but to me it would appear that this approach doesn't fit with the objectives of the forum. As @Will Prowse states in his guidelines... "Vendors can still post here on the forum, but they cannot promote themselves in any way" and "Keep in mind that we volunteer our time here, because we love electronics and DIY solar projects. The exchange of information on this site is fantastic, and it will always be free for everyone."
 
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