Dear community,
we are currently trying to reduce the noise level of our Quattro-II 5000, as it is located close to our living area, and producing a more-or-less constant and loud 50Hz hum (the fan is less of a problem). We will install soundproofing mats and dowels, as has been recommended on this forum.
By coincidence, I just met solar professionals, who told me, that the noise is likely the result of a configuration problem. I am doubtful of that, as the hum was there from day one - also, posts on this forum seem to suggest that the humming is pretty normal for this device. But still - are there settings in VE.Config or the Cerbo GX, that could lead to a reduction of the humming?
In fact, sometimes the humming disappears for a half a minute or longer, so generally it is possible for the device to work silently - then again gets louder gradually.
When I switch off mains, and run on batteries, the noise level is much lower, almost silent.
Loads on the other hand do not seem to make a difference - the humming is there even when all loads are disconnected, it is also there when idle (not charging or charger switch off in VE.Config).
One thought was that it could be due to a low quality of the AC IN (we are based in Ukraine, so who knows), but settings such as Weak AC On, PowerAssist Off, UPS Off did not have an effect on the noise.
Otherwise, the Quattro-II is controlled by the Pylontech BMS (state "External control", the Quattro-II mostly lights BULK or ABSORPTION, but according to the chart it sits idly on "External control", battery at 100%, not charging).
Thank you for suggestions