MultiPlus-II 48/8000 prefers grid instead of inverting, makes repeating humming noise at night

DIY
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1

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Hello,

I have a Victron MultiPlus-II 48/8000 with Dyness batteries. My problem is that the inverter seems to prefer grid power instead of inverting:

  • It switches to grid for about 1 minute,

  • Then back to inverting for about 30 seconds,

  • Then back again to grid,

  • This cycle repeats constantly.

During each switchover there is also a humming/buzzing noise, which is especially disturbing in the middle of the night.

To stop the noise I have to manually disconnect the grid.

The strange thing is that at my parents’ house they have the exact same system, same firmware, same settings, and theirs works normally without this problem.

:backhand_index_pointing_right: My question:

  • Why is my MultiPlus-II preferring grid and switching back and forth like this?

  • Is there any setting (ESS, UPS function, grid code, etc.) that could fix this?

  • Can someone share their working settings for MultiPlus-II with Dyness batteries in grid-connected mode?

Any help would be much appreciated, as this issue is getting very annoying.

Thanks!

2

You already have the requited settings, this according to your own description of parents exact same system with same settings working ok.

This would indicate a physical difference, maybe poor connection / batteries unable to hold load / damage somewhere as potential issue.

Screen shots of what the system voltage / load ect at time of issue would maybe help.