A Multi 3kVA installed over a year, recently began making random hum/buzzing noises that verge on vibration sounds. I have sound bites from the customer and I've not heard it before. System seems to still be operating correctly.
Doesn't seem likely anything has changed with the installation - is there a known issue with the Multi that can lead to these noises?
Thanks for the suggestions - it does sound like an electrical noise from the audio clips sent through. Will ask the customer to isolate loads on AC Output. And check vibrations on the chassis.
Is it more likely to be the transfer switch playing up rather than the inverter?
System is an ESS system in grid parallel I believe so will be feeding power form AC Input as well. Presumably the Multi is less affected by power factor loads on the AC Input side?
I'd start by switchin off loads to see if you can find what is causing the noise (and if it makes this noise without anything connected, contact your distributor for warranty repairs)
Is it getting better while pressing against the front? Retightening the screws could probably be a very simple solution then.
I had a Quattro that had a fan go bad, buzzing like crazy. You might check that first.
Loads which have a poor power factor will cause this, that is why Boeiel suggests isolating loads one by one.
Does this issue persist with the AC in disconnected?........
Could potentially be, and Sounds like “relay chatter”,
Where a relay or transfer switch is operating at 50 times a second causing the vibration which can be heard.Ive come across this before in a unit,follow Boekel’s advice and see if the issue remains with loads isolated
