So I built a system with all Victron components - LFP Smart Batteries, Multiplus, Cerbo, BMV-712. It's working great, but... Only now am I finding out that the VE.Bus BMS doesn't allow me to control the inverter on/off state through anything but the Digital Control Panel which is really annoying.
Is there any alternative BMS out there I could use that would be similar to the VE.Bus BMS? I don't have room or the option to use the new Lynx Smart BMS, so that is off the table.
I've designed a BMS that runs on a Raspberry Pi under the Venus OS. The Pi has 4 relay outputs which can be configure to control the inverter on/off/charge only - so this wired function could have a manual switch added. This was based on the work by Louis van der Walt, so have a look at his Github pages. There are quite a few alternate BMS systems out there....
This one major downside to the ve.bus BMS. There was plans to have this resolved in a Venus update, but that was removed last minute. I'm not sure where this stands. The only other option that I could see working for you with the Victron batteries would be the MiniBMS then wire the two wire assistant to the Multi. However I think you'll need to wireup an optocoupler to multi as I'm not sure if the outputs are isolated.
smallBMS with pre-alarm - Victron Energy
I've never used this, but this is a victron product which might do the trick though I've never used it before:
Orion-Tr DC-DC Charger Isolated remote cable - Victron Energy
You would take the output of this, and wire it to the aux1 and aux2 ports. Then install the assistant on the multi. Seems like a lot of extra work. Hopefully Victron can revisit this option on the ve.bus bms and Venus.
Manual-Connecting-other-lithium-battery-systems-to-Multis-and-Quattros-EN.pdf (victronenergy.com)
I see. Yeah that is quite the bummer they didn't implement that functionality. It's especially disheartening since clearly you can still control the Multiplus with the digital multi control with a ve.bus bms in the system. Not to mention this exact setup is shown in a ton of their system diagrams, and ve.bus bms is the 'recommended bms for use with inverter/chargers' on the lithium battery page: https://www.victronenergy.com/batteries/lithium-battery-12-8v
This smallBMS might be a good option, not too expensive either for an experiment. Really, I just wish they would take the time to support this product.
As far as I know this is a limitation of the VE.Bus protocol. If it where possible to implement this feature Victron would have done it.
I would support some kind of workaround, even if it was to plug the cerbo into the DMC panel plug on the ve.bus BMS like you can do with the DMC.
Everything else in the Victron System works so nicely together, with a high level of polish. Its just such a bizarre thing for this not to work, or to have been missed by the design team before it was launched, or whatever happened to end up here.
What about the Lynx BMS as an alternative? It's expensive but I haven't read about the limitations present with the VE.Bus BMS.
Personally, I can't see why a GX device can't do what the DMC can do. This limitation disqualifies the Victron batteries for any system I would design.
I'm going to try the smallBMS + two wire assistant in the multiplus as has been suggested elsewhere.
