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VE.Bus BMS verses smallBMS and signalling charge disconnect to MPPT controllers

As I continue to investigate the possible connection options to get my system working as I require and following on from my question about VE.Bus BMS verses smallBMS. I hope someone can help with this part of the communication flow and if any functionality is lost be using a smallBMS verses a VE.Bus BMS.

I am aware that the Cerbo is able to signal via VE.Direct or VE.Can to connected Smart MPPTs that a charge disconnect event has happened. This is confirmed in this post where Guy has stated "Yes, it works. The VE.Bus BMS will signal to the Multi on the VE.Bus, and then that will be sent to the GX device which will control the MPPTs via VE.direct or VE.Can (>2019 models only) cables."

However there is nothing about the smallBMS. The above post has a link to another post where Matthijs says "Regarding connecting: the Venus GX cant retrieve data directly from the VE.Bus BMS. So, even though they are on the same network (VE.Bus); you still need an inverter/charger in that same network to make it work.". This implies to me that the MultiPlus sends the charge / load disconnect to the Cerbo and not the VE.Bus BMS itself.

While I have a VE.Bus BMS at present it is not connected to the VE.Bus and I am using a 2-wire assistant on my Multiplus. The Cerbo shows this and when the pin on the VE.Bus BMS goes high, the Cerbo state changes too yes. So I know the Cerbo is getting the information.

So the details are getting to the Cerbo. Therefore with a smallBMS or VE.Bus BMS using 2-wire assistant, will the MPPTs still get a charge disconnect via VE.Direct or VE.Can. I am unable to test at the moment as while my MPPTs are installed the Solar panels are not yet installed.

I would like to know if when using the smallBMS, the VenusOS will still signal charge disconnect to the MPPTs, and how I can tell if the signal is getting through to the MPPTs. For info I have two VE.CVan 150/70's connected via VE.Can.


Venus OSBMSVE.BusVE.Can
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