A strange Multiplus/Node-Red behaviour

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1

I’m experiencing an issue with my Victron /node red setup.

My Node-Red is set to change the Multiplus state from “charger only” to “inverter only” after the night time charging cycle.

However, when I wake up the next morning, I always find the Multi in the “ON” state instead.

  • To clarify the situation I can explain how my charging cycle is setup:

  • Here is what it looks like:

  • 09-REVISED-Charge Profile copy
    09-REVISED-Charge Profile copy1701×867 278 KB

    1. My AC-In is always set to “ignore AC-In” which only becomes active when one of the Multiplus’s digital input is triggered to “Generator-Start” by the Cerbo’s relay.

      • NODE_RED

    2. An inject node sets the inverter to charge only mode at a specific time. (this also triggers the external transfer unit to change from island to grid)

    3. This causes the AC- out to disconnect passing the grid through as soon as the Gen-Start signal triggers the AC-In ignore to “off” (allowing the pass through)

    4. An external timed relay activates connecting the AC-In to the grid

    5. At this point Linx SOC, subject to the time setting, commands “Generator ON” finally completing the cycle.

    The opposite happens when charging needs to be interrupted avoiding high tariff times so:

    1. First the Gen is turned off by Cerbo

    2. Then Node Red’s Injects an “Inverter only” to the Multiplus

    3. Finally the external relay fully isolates the AC-In which had already gone back to “Ignore AC In”

    (The external relay is an extra precaution as I’ have noticed that, even when in Ignore AC In state, the VRM shows the AC-In voltage as active)

    The reason for this setup is that my solar shed is about 90ft from the grid service point and I cannot, or want, to divert the grid all the way there to come back to the property having to go through the Multiplus continusly.

    I want the property to remain with the original setup and in compliance.

    A transfer switch takes care of what the Multi would do if used conventionally.

    So, if Node-Red’s inject node sends the “inverter only” signal at the end of the cycle but in the morning I always find the Multi in the “ON” state instead, why?

    The question is, what else can override the inject’s “inverter only” command I ask?

    Any idea out there?

2

I think I might have found the culprit:

After having removed the SOC gate, the issue disappeared.

I now have to investigate why