Multiplus II 48/5000/70-50 short loud buzz and voltage drop

DIY
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1

For no obvious reason, with a ~130W load, the inverter made a short loud sound, and the external voltage relay (low threshold: 185V) disconnected the load. The inverter was disconnected from the grid and running on battery power. There were no alarms or notifications in Venus OS or the battery BMS.

Link to the video - https://drive.google.com/file/d/1MCMCfPi9eSVT8bmwtz_pvxV6Ss-53PiS/view?usp=drivesdk

If anyone has any ideas what it might be, I’d really appreciate it.

2

Hi aleksbyhun,
Welcome to the community!

I’ve found a couple of things that might be helpful, but if not, perhaps someone else in the community will have a solution.

Loud humming noise and voltage fluctuations - DIY - Victron Community
Multiplus II - Inconsistent sound and energy | DIY Solar Power Forum
Dave