We are running a Victron MultiPlus II GX setup and don’t understand what’s causing the inverter to switch off.
Some of the configuration details:
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ESS Assistant enabled
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Battery type and voltage limits configured in VEConfigure
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Grid and inverter voltage limits explicitly set
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We feed the ESS the inverter setpoint via Node-RED according to PV surplus or demand.
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We have not programmed any mechanisms in Node-RED for switching inverters etc. on and off.
Observed behavior (intermittent):
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Roughly once every 2–3 weeks, the system shows unexpected behavior.
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The system charges the battery normally until 100% SoC is reached.
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Charging then stops as expected once the battery is full.
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A few hours later, ESS requests discharge.
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At that point, the inverter state is “Off”, not “On”.
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As a result, discharge does not start.
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The inverter must be manually switched back to “On” in the software to resume normal operation.
Key issue:
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The inverter appears to switch from “On” to “Off” without any manual action.
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We do not understand what triggers this transition to “Off”.
Additional observation:
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Not always but only once: In the VRM Portal, shortly before the inverter went to “Off”, the VE.Bus State frequently toggled between Bulk and Absorption multiple times.
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I see that the battery’s reported charge current limit was already zero before switching off but not sure if that is part of the problem.
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After this phase, the inverter ends up in Off state.
Screenshots from the VRM Portal are attached to illustrate the VE.Bus State behavior prior to the issue.
Question:
What conditions or internal logic could cause a MultiPlus II GX to switch itself from On to Off without user or Node-RED interaction?
Any hints on where to look (settings, protections, ESS behavior, firmware-related causes) would be appreciated.
