Hello everyone,
I am designing a new self-consumption ESS system for a building with two separate apartments, each with its own grid meter (Meter 1 and Meter 2). I would like to use a single, shared battery bank for both.
This will be an In-line setup (Grid meter > Multi RS [AC-In] | Multi RS [AC-Out] > Apartment 1 Loads), and I do not intend to export any energy back into the grid.
Current proposed setup:
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System 1 (Apartment 1): Multi RS Solar 48/6000 connected to Grid Meter 1. It will manage the PV arrays and a battery bank (via Cerbo GX) consisting of 3x Pylontech US5000.
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System 2 (Apartment 2): A second inverter (considering a MultiPlus-II) connected to the same battery bank and to Grid Meter 2.
The Goal: Both apartments should operate in ESS mode, prioritizing battery power. Apartment 2 should be able to draw from the shared Pylontech bank until a set SOC is reached, then switch to its own grid (Meter 2).
My questions/doubts:
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Communication Mix: The Multi RS uses VE.Can, while the MultiPlus-II uses VE.Bus. Can a single Cerbo GX effectively manage both in an ESS environment where they share the same DC bus and battery data from pylontech bms?
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Future Scalability: I might need to add a third apartment (Meter 3) in the future by adding a third inverter to the same DC bus.
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Alternative Suggestions: Is there a better way to achieve this (sharing one battery between two independent AC-in sources) within the Victron ecosystem?
Thank you in advance for your insights!
Clarification:
My initial intent is to start with a basic setup, featuring a single grid meter and one apartment. I’ve chosen the Multi RS because its specifications (power output and MPPTs) perfectly match my needs; it supports ESS and offers an all-in-one solution. Additionally, I’ll be using a Cerbo GX to integrate the Pylontech BMS into the Victron ecosystem.
Grid Meter 1 will be directly connected to the AC-In and the apartment 1 to the AC-Out of the Multi RS.
Future Expansion: The second phase involves adding a second inverter, like a MultiPlus-II (MP2), to power a second apartment with its own grid meter. My logic for the MP2 integration (which may need a reality check) is as follows:
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Discharge Only: The MP2 will be configured to never charge the battery pack; it will only discharge to cover the loads of Apartment 2.
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Grid Dependency: The MP2 will draw energy from Grid Meter 2 only when the batteries fall below a specific SoC or when the total power demand exceeds the battery pack’s discharge limit.
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Centralized Management: Both inverters will be managed by the same Cerbo GX to regulate power draw and monitor the system.
My Question:
- Communication: Can a single Cerbo GX effectively manage both the Multi RS (via VE.Can) and the MultiPlus-II (via VE.Bus) simultaneously while reading data from one Pylontech BMS?
I would appreciate any advice on potential pitfalls