YamBMS JK-BMS-CAN with new Cut-Off Charging Logic (open-source)

[erepeo]

Do you know why the balancing status does not always refresh correctly? I’ve noticed that the balancing current is present in one of the entities, yet the "balancing ON" status remains "OFF." Conversely, when there is no balancing current, the previous status sometimes remains instead of updating.

 

[SomethingAppropriate]

Do you know why the balancing status does not always refresh correctly? I’ve noticed that the balancing current is present in one of the entities, yet the "balancing ON" status remains "OFF." Conversely, when there is no balancing current, the previous status sometimes remains instead of updating.

I noticed that too and I am not concerned. I dont think polling that data more often would be worth it.

 

[erepeo]

I have a different opinion. This parameter is helpful. Sometimes, the update takes several minutes.

 

[jb3112]

Note to my self, remeber to read all

 

[erepeo]

Has this behavior of this entity been described somewhere? If so, please advise because I haven't seen it anywhere.

 

[erepeo]

Does anyone know if it is possible to communicate the Easun SMW 8kW inverter
(this is the same as the Axpert AXMAX8K48V) with YamBMS?

I am asking because I want to recommend YamBMS to a friend but I am worried whether it will be possible.

 

[Sleeper85]

Does anyone know if it is possible to communicate the Easun SMW 8kW inverter
(this is the same as the Axpert AXMAX8K48V) with YamBMS?

I am asking because I want to recommend YamBMS to a friend but I am worried whether it will be possible.

No, because Voltronic inverters don't support the most common CAN protocols like PYLON.

They support PYLON over RS485, and that's something I haven't developed yet.

 

[Sleeper85]

Do you know why the balancing status does not always refresh correctly? I’ve noticed that the balancing current is present in one of the entities, yet the "balancing ON" status remains "OFF." Conversely, when there is no balancing current, the previous status sometimes remains instead of updating.

All I can tell you is that an issue has been detected on the esphome side.
This concerns incorrect entities synchronization when there are a large number of entities, as is the case with YamBMS.

This issue does not seem to occur when the logger level is set to DEBUG.

Furthermore, this bug seems to have been fixed by the PR below.
If you are using YamBMS 1.5.4, I have added this PR to the code.

[api] ensure fair network sharing + prevent lost state changes via deferred publish at high event load by nkinnan · Pull Request #7547 · esphome/esphome

What does this implement/fix? If the API buffer is full, instead of dropping messages, put them in a deferred send queue. Once there is buffer space, the latest state from the component that misse...

github.com

Which BMS model are you using?

 

[erepeo]

I hope you don’t mind me asking this—I realize this topic may have been discussed before, but I couldn’t find the exact information I was looking for. I really appreciate any help, and I don’t mean to come across as someone who just asks without searching. If I missed something, I apologize, and I truly appreciate your time and assistance.

I’m currently using YamBMS version 1.5.1 along with a JK BMS B2A20S20P.

 

[Sleeper85]

I hope you don’t mind me asking this—I realize this topic may have been discussed before, but I couldn’t find the exact information I was looking for. I really appreciate any help, and I don’t mean to come across as someone who just asks without searching. If I missed something, I apologize, and I truly appreciate your time and assistance.

I’m currently using YamBMS version 1.5.1 along with a JK BMS B2A20S20P.

Make a copy of the latest YAML available on GitHub and compile again.
You will be on 1.5.4 and probably the entity refresh issue will be resolved, I hope.

 

[erepeo]

Make a copy of the latest YAML available on GitHub and compile again.
You will be on 1.5.4 and probably the entity refresh issue will be resolved, I hope.

I've done my first tests on version 1.5.4
Now it works fine. Thank you!

 

[b1ggi]

I understand that it might not be possible directly in the BMS, but I’m asking specifically about YamBMS. My question is whether a "box" for entering such a value will be added in an update, or do you mean manually modifying the code on my end?

Hi, i want to pick up on this topic.

Inverter BMS battery capacity not reporting correctly · Issue #535 · syssi/esphome-jk-bms

I connected a 250Ah battery and all data seemed correct between JK BMS App and ESP. Somehow this changed and the ESP battery capacity sensor is now reporting 161Ah while the BMS still reports 250Ah...

github.com

i reset my capacity to 280 because of a display error, and my cycle count and cycle capacity are reset to 0.



could you bring in a manual setting for cycle count and cycle capacity tied to the bms, so i can have a correct history tracking and SoH calculation and calm my OCD? :D

JK does not support setting cycles afaik.

 

[SomethingAppropriate]

Hi, i want to pick up on this topic.

Inverter BMS battery capacity not reporting correctly · Issue #535 · syssi/esphome-jk-bms

I connected a 250Ah battery and all data seemed correct between JK BMS App and ESP. Somehow this changed and the ESP battery capacity sensor is now reporting 161Ah while the BMS still reports 250Ah...

github.com

i reset my capacity to 280 because of a display error, and my cycle count and cycle capacity are reset to 0.



could you bring in a manual setting for cycle count and cycle capacity tied to the bms, so i can have a correct history tracking and SoH calculation and calm my OCD? :D

JK does not support setting cycles afaik.
View attachment 285835

View attachment 285834

The cycle count is only set on the bms.
So we world either use a fake count or the actual bms count.

 

[b1ggi]

yes im asking for a manual additional fake cycle count and cycle capacity to the reported value from bms (which represents the real cycles).
Yambms for me is a solution to enrich the shitty software solutions from the chinese bms manufacturers, and it solves a lot of problems.
i dont think we can hope for a cycle count setting from the bms manufacturers (JK in my case).

 

[Daddy Tanuki]

yes im asking for a manual additional fake cycle count and cycle capacity to the reported value from bms (which represents the real cycles).
Yambms for me is a solution to enrich the shitty software solutions from the chinese bms manufacturers, and it solves a lot of problems.
i dont think we can hope for a cycle count setting from the bms manufacturers (JK in my case).

honestly cycle count means nothing on these cells if you follow the rules... 90% to 10% between the temps of 10-30 deg C.. you will calendar age them out before you run them out through use.

 

[Sleeper85]

@b1ggi

[FEATURE REQUEST] correct the BMS cycle count · Issue #35 · Sleeper85/esphome-yambms

Requested by b1ggi. Add the ability to configure an initial cycle count, which will be added to the BMS cycle count. This would be useful in case of a BMS reset or replacement.

github.com

I added it as a feature request, I'll do that the next time I work on the code.

I'm currently busy with another project.

 

[jb3112]

Is it working corrwct in comes with COCP warning and stop charging and then it go away and start charging But Only op to 100A
Havnet could find any in this trend about it. Is there settings that is not correct

 

[michu_m]

hello
I have 9x Jk-B2A24S15P, I would like to monitor them, can you advise me on the best way to connect it, whether via UART or otherwise supposedly has RS485/CAN, please suggest.

 

[Sleeper85]

Is it working corrwct in comes with COCP warning and stop charging and then it go away and start charging But Only op to 100A
Havnet could find any in this trend about it. Is there settings that is not correct

If your BMS displays a Charge OCP alarm, it means your charging current appears to be exceeding the maximum charge current set in your BMS.

If you're only using YamBMS with an AIO unit, this shouldn't happen because you can only request 90% of your maximum charge current.

However, if you have additional chargers, it may be possible to exceed the charge current.

Tell us more about your system, devices, and configuration.

 

[Sleeper85]

hello
I have 9x Jk-B2A24S15P, I would like to monitor them, can you advise me on the best way to connect it, whether via UART or otherwise supposedly has RS485/CAN, please suggest.

Only monitor them or use YamBMS ?

Solution 1) Use a single ESP32-S3 and UART expansion boards (like PVbrain2)
Solution 2) Use multiple ESP32s / ESP32-S3s

• ESP32 can monitor 2x BMS via Bluetooth
• ESP32-S3 can monitor 3x BMS via Bluetooth
• ESP32 / ESP32-S3 can monitor 3x BMS via UART

If you want to use YamBMS with solution 2, you need to set up a multi-node solution (max 2x BMS UART per ESP32)

 

[shvm]

I concede that this must have just been coincidence, I'm unable to replicate it again, but it does seem like fiddling with YamBMS controls eventually gets it to start working. I think I'm going to enable float charging anyway and maybe that will keep it from ending up in this state.

Someone at LuxPower needs to look at it. It comes on after I update BMS firmware, stays for ten-twenty minutes and then goes away

 

[shvm]

I tried changing 'min_value' and recompiling, but the previous values remain in HA.
As it turns out, without the Lux SNA built-in functionality to export from the battery, I can achieve some battery export by lowering these values below the current battery levels.

I am completing an year of grid export with my SNA unit. All it takes is limiting charging current limit, to 0 or some lower value. The inverter will feed the rest of the excess power.

 

[Dmode]

I am completing an year of grid export with my SNA unit. All it takes is limiting charging current limit, to 0 or some lower value. The inverter will feed the rest of the excess power.

If you simply reduce the charging current to 0, the PV will go to export, but there will be no export from the battery.
Here’s what I meant:

• A regular situation (PV goes to charging) when a CAN request for a charge voltage higher than the current battery voltage.

• Battery export when a CAN request for a charge voltage lower than the current battery voltage.

This became possible thanks to YamBMS, after @Sleeper85 explained how to reduce the lower range of the charging voltage.

 

[Dmode]

Someone at LuxPower needs to look at it. It comes on after I update BMS firmware, stays for ten-twenty minutes and then goes away

On your screenshot, the BMS status is "charge forbidden." In my opinion, this is the correct response of the inverter to the loss of communication with the BMS when you are updating the firmware. And this status is indeed cleared only about 10 minutes after the battery transmits via CAN that everything is OK.

 

[shvm]

On your screenshot, the BMS status is "charge forbidden." In my opinion, this is the correct response of the inverter to the loss of communication with the BMS when you are updating the firmware. And this status is indeed cleared only about 10 minutes after the battery transmits via CAN that everything is OK.

I figured something close to this today myself. Everytime I OTA the ESP, the inverter flashes a voltage of 65.536 V on the display and forbids charging. What a waste of energy!

In my opinion, this is the correct response of the inverter to the loss of communication with the BMS when you are updating the firmware. And this status is indeed cleared only about 10 minutes after the battery transmits via CAN that everything is OK.

People at Luxpower should allow users to override this behaviour

Battery export when a CAN request for a charge voltage lower than the current battery voltage.

However, be aware that it is merely the inverter trying to discharge the battery to loads (in order to lower its voltage)
The only power being exported is generated by Solar.
Will Work for discharging a fully charged battery by day, won't work at night.