Hello, I have a fully functioning ESS system with 3 phases from Victron, everything works great in stand-alone mode. I still have 3 Victron Multiplus and a BMS lying around. My question is, since I don’t have any more space, I would like to build 2 Victron ESS without solar as a 3 phase system with batteries. My idea was, if possible, to add the 2nd system and when the batteries in the 1st system are full, to use the excess current to charge the 2nd system. Is it possible to program and install it like this? Regards

A comment from me on another topic But the function principle is nearly the same: [image] For you the system A should also be a ESS with Meter. On top of this vou would need a second Hager SFT440 (or something else) to switch the Input if the two systems to the grid (if system A fails or while maintenance).

I’m doing exactly the same in my setup You may see it in other thread [image] Dynamic ESS, PV coupled, facade & roof PV fields Show us your system Full video about what I was able to accomplish in NodeRED in order to control planned/unplanned grid outages use Excess solar in second system to charge batteries Automatically update prices in DESS Overcome Passthrough mode in MultiRS when VM meter is offline See video [NodeRED + DESS + Excess Solar usage - Victron automation on steroids]

Hello again, my plan would be for everything to run fully automatically. As soon as the primary ESS has 100% battery, the solar power should be used to charge the secondary ESS. The rest is in the picture. What would the programming or wiring for the AC side look like? [ESSVIC]

Sorry i am not stupid ESS Primary hast 100kWh storrage thats the maximum and i will not throw away 3 good Multiplus Inverter / Charger

I have also no more space, and i have still only 2 Years old Multplus 24/3000/70 + 5 BMS + Gerbo GX. thats the reason i am asking to combine 2 ESS systems, and how wir [photo_2024-12-13_18-26-41] ing must look like

I’m using NodeRed where in primary ESS I’m detecting solar excess, sending mqtt message to secondary ESS, where switching to “keep batteries charged” Once on primary ESS battery falls to less than 95% SOC - toggling secondary ESS back to “optimized without BatteryLife”

Sounds good can you tell me more :slight_smile:

Here is a video, where I’m covering slightly part of excess solar usage https://youtu.be/RQNFCH41R9k I’m sending signal from first GX to second GX where by reacting on it I"m changing to “keep batteries charged”

May I Ask how you wired the 2 ESS Systems?

Sure I have 2 Cerbos, mqtt for sending messages between 2, NodeRED for getting and sending on first, NodeRED for receiving and acting on second one.

Second Victron ESS as Backup-System

Q&A and troubleshooting

podarok (Andrii Podanenko) 9 December 2024 20:24 3

I’m doing exactly the same in my setup

You may see it in other thread

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Second Victron ESS as Backup-System

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