WTB: 4s DIYBMS 4.4 complete setup

I just stumbled on the diyBMS and I’m blown away by what Stuart has done. I love to tinker with BMSes and while I’ve been happy with my electrodacus, for a future system I’d love to have CAN integration with my victron gear. However I am terrible, terrible, TERRIBLE at soldering. I know he doesn’t do commercial sales but I’ve seen stuff pop up from time to time and just thought I would throw out my interest in a full 4.4 setup with four monitor boards, main board and shunt board. Thanks!

If you are in the USA I have a couple shunt PCBs and will have a few module PCBs available in a couple weeks (order is in production currently).

Unfortunately the controller PCB will be problematic as there are shortages on many of the ICs. If there is enough demand for controllers I can look at sourcing parts and doing another group buy, but the prices will likely end up slightly higher due to the current shortages.

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Hey Mike,
I just checked my Controller board BOM on JLCPCB and it’s still showing the following shortages:
U1, U3, C3, C4, & U8. Same as it was 6 months ago.
I’ve moved ahead with Batrium for the current POC project but we still want to finish the diyBMS setup regardless. Everything else is done, we just need the controller.
The goal of our off-grid container proof of concept was to be 100% DIY, open source, & recycled/refurbished so we still have to put Stuart’s solution back in at some point.
In short, we’re open to helping do a group buy of some sort to help this along if you’ve got any ideas. I’m even open to pre-buying a couple of reels in the 1000’s at JLCPCB if we can’t find some alternate components for the BOM.
Let’s talk after the first of the year.
Thanks,
Tom

It’s unlikely to change anytime soon sadly.

  • C3 and C4 can be swapped for C122265 which they appear to have in stock. If not, the component is large enough for hand soldering if necessary and can be sourced elsewhere.
  • U1 (TJA1057GT/J3) has been extensively discussed in TJA1057GT/3J · Issue #83 · stuartpittaway/diyBMSv4 · GitHub. There aren’t many alternative options available in stock. This at least is not a critical component to have except for Victron CAN based communications.
  • U3 (TCA6408APWR) possibly PCAL9554BPWJ with a few adjustments to the code.
  • U8 (TCA9534A) possibly PCA9500PW with a few adjustments to the code.

U3/U8 can also be sourced on AliExpress but it is a gamble on if the chips are rejects/fake/etc.

I am in the US (Las Vegas) so I’d be happy to pick up a few of your extras! As for the TJA1057GT/J3 I would that as I need victron CAN. I would build a test setup before install to assist with whatever Stuart would like me to test if needed. I was hoping to build a zerotier network on an isolated vlan that I could provide to Stuart so he could log into my network if needed since he doesn’t have victron gear. I haven’t mentioned that to him of course but that was the first thought that came to mind when I watched his video. :slight_smile:

Drop me a message on here and we can arrange the details, I am not 100% certain how many extra modules there will be but I should at least have a couple shunt PCBs.

Yeah, you would certainly need it in that case.

Let me post in a generic topic to find if there is enough interest in another group buy of PCBs and I’ll take care sourcing parts and PCBs to do so.

Thanks Mike. I appreciate the break down on the possible alternates available. I may have to do that in the interim.
But I’m still interested in going in on a group purchase if that’s in the cards and there are enough people who want to join in. I can’t imagine it would be very hard to find 4 others since we have to order 5 controllers as a minimum.
Let me know if you have any other ideas.
Cheers,
Tom