Big update on this. I have removed the old 1.5 kWh storage system and now rely solely on the Sungrow inverter to shift all the power around
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I connect V2x and the stationary battery via a changeover relay. It would be great to change over from the stationary to the car battery ...

Get me out of here, I don't want to deal with LDU and SDU again!

Yes it's not like anybody really got on top of about it but seeing the sad face when you tell people they have to buy a new inverter is priceless in a negative way. And then you can't even say why it happened and how to really ...

There is too many threads on this already, locking up
search.php?keywords=+ESP+and+STM

Will try playing with those resistors the next time I open the bike up, thank you for the advice!

Just found there is a software way to do it. Right now the lower two FETs are closed for dissipative balancing. That is via the 2x10R resistors. If the upper two FETs are closed it would skip those ...

Interesting. Are you turning on power to inverter and ESP simultaneously?
I wonder if it times out fetching the serial number or something. Then when changing speed or node id the request is repeated and all is well.

Always use the correct tools when working with HV

Now after running 6 modules in my ESS for some weeks with old, high R_int LFP batteries there are some observations:

- it is dead stable, even over multiple power cycles and even with some 2.1 modules in there
- SoC calculation is all over the place. Sometimes it estimates when there's still ...

Was just setting out to do the same thing but just modding the ESP web interface to run locally and use oic as a backend.

How hard would it be to add a "dumpjson" command that outputs the json updated with the recent values? Maybe even likewise for the CAN maps?

Pretty cool idea. Since balancing only makes sense when there is no current flow there is also no risk of missing an over voltage event.

I have moved the now closed source CAN hacking here: viewtopic.php?t=6497

Can I downgrade the v2.4 BMS version or that is not recommended? Even if I can make it show 47.4% it would not look good on the screen and is not needed.


No way, pre-0.26 has to little dead time and will fry the FETs for sure. You can add a new custom mapping for SoC or change your display ...

On previous version for BMS I was getting 2 digits for SOC. now with the new boards I am getting 3 digits. is that something you changed on the latest code? 0.26R

Yeah that was a sort of recent change to show more resolution.


I read your thread about giving up inverter projects and thought ...

Hmm, interesting. How many Ah did you say they are?
You can also try playing with R23 and R28, down to completely bridging them. Then only the 10R (mostly 2 of them on most channels) inline resistors limit the current.

I let my LFP pack sit for one week and it improved from 55 to 20 mV. Those are ...

Yeah fair point. The black cables are double insulated but the red one obviously not. Will adjust that.

I had these pre-crimped wires handy but they limit me in length so BMS sits on top for now

It's great that you are very thoughtful.
As for me (OI shop) I don't sell M3 boards and not planning either.

Yeah it's outrageous how much they've come down! If you buy a palette of 36 it drops towards 50€.

Just found I never shared this here.
So since 2014 I've have various kinds of solar panels on the balcony, right now 500W on one Enecsys inverter and 350W on some other one.
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Then I added various panels onto the garage roof of the garage I don't even rent ...

Just the inverter project.
This backup idea might still be worthwhile. Right now I just pull a complete file system and data base backup to a local raid array.

Well I guess that's great but please don't plant the seed to political discussions. There's other places for these.

That is for the future maintainer to decide

Thanks for speaking up.

So, the inventory:
- West side EV already sells SDU and LDU kits
- A Californian citizen is offering to take over HW/SW development AND board distribution
- You also want to distribute boards

So in the US we have 3 (potential) distributors, in Europe none. Lets see how we ...

yes https://github.com/jsphuebner/stm32-sin ... 8467104886

Oh wow, well thanks for the insight.
I'm not totally against incentives but they need to be done right.
- Currently we have subsidies for heatpump installations and magically they cost twice as much as in France
- We used to have direct EV subsidies of 6000€. Dacia Spring cost about 5000€ less in ...

Proton wrote: ↑Sun Jun 22, 2025 3:15 am I guess that heat indeed has a big effect on the solar panels

Yeah it does. It was 30°C here yesterday and my system peaked at 1070W. On sunny cold days 1250W

Yeah that is intended. In this time it can do balancing. After two hours it should power off, although there is still some bug that I will fix next (the sub modules don't power off)