My 2.5 year old MultiPlus has slowly developed a fault where over the last 2 months, when it started disconnecting the grid for no apparent reason. No warnings or messages on VenusGX console or VRM. The unit is installed in a motorhome, it's been working fine for more than 2 years and every few days I'm connected to a new 16A AC230V supply (via a "UK" caravan socket) at various campgrounds. This behaviour seems to happen irrelevant of location (and thus the quality of the grid supply is not the problem). The fault is when I start using some AC230V loads in pass-thru mode (without using the inverter), I could hear sparking inside the multiplus, coming from the bottom right corner, and eventually something in the multiplus trips (distinct click can be heard) and MultiPlus starts inverting to supply the load, which then works fine. After sometime something clicks again, and it the cycle starts again...
Here is an example (1 minute), with grid connected, powerassist OFF, current limit set to 0A (so that charger is taken out of the picture, and pass-thru is forced). I connect a 1000W fan heater - hear the sounds coming from the bottom-right corner of the MultiPlus:
https://www.youtube.com/watch?v=iIPu9M-f6K8
Somebody please tell me whether this is normal or not, and what could possibly be the problem? I would like to tell the service centre where to start looking...
The service centre says they found no problem with it... It's not like I would go into all the hassle pulling the unit out, sending it via courier, waiting for it for 1.5 months, while stuck at a single location, as I have no way to charge my batteries other than solar right now - just to hear "there's nothing wrong with the unit". Anyone had a similar experience with Victron's authorised service centre taking over a month to "look" at the issue and then telling you that there is no fault? What can I do to escalate it?