This is from this post. Super lame forum migration Victron.
https://community.victronenergy.com/questions/293961/multiplus-12200080-fan-ticking-noise.html
Does anyone have the infamous fan ticking noise?
They actually replaced the entire unit on warranty and the fans still tick when bulk charging. It’s impossible to sleep or work in the van.
Desperate for suggestions or mods. Thanks.
Not sure if my cheap phone video picks it up, but it’s loud enough to hear through the closet at night.
Hi sounds like a wire or something is touching the fan, could also be that the fan is to tight or twisted in the housing
Nope. I’ve checked all that
Out of curiosity, what firmware is it running. I have that model and don’t hae the issue.
v510
It is strange. That sound is usually related to a sine wave chop.
What is sign wave chop? Something I can test and fix? Is it bad for the unit or my batts? This is my second unit that hums loudly and fan ticks. Drives me nuts.
Sorry bad English was used. The same sound is made when only half a sine wave is there such as when a triac based device is being used.
Checking the sine wave requires an oscilloscope.
The hum is normal for a transformer based inverter.
How comfortable are you with opening up the unit and checking that everything is plugged together well?
Very comfortable. Inspected. Everything looks good to me. The humming is fine. The ticking is infuriating.
And your input connection for charge, is it long and what gauge is it? Does it change if you alter that or input current?
It’s a 50amp shore power cable. However, I am often using an adapter to a 110v outlet. If I recall correctly, the hum still persists when plugged into a 50amp or 30amp service.
I still dont think it is the fans.
Put the silence fans assistant on.
Obviously watch for heat.
Ticking can happen in power supply and transmit through for a large number of reasons.
Ok. Thank you for your input.