question

What about the connection to the battery?

Maybe a blown fuse?

@MattFR please provide the Breaker type MCB RCD RCBO AFDD? Are you in the UK?

There are two breakers, 32A type B mcb on a ring final circuit in the workshop where the Multi is plugged in, fed from a 40A type B mcb on the house consumer unit. Both trip when the Multi relay pulls in. I was running it without this problem the day before, so it makes me suspect the Multi, as I'm not aware of any other changes.

Oh, yes, I'm in the UK.

OP your a 100% that's an MCB? any chance of a pic, seems Strange that both would trip and MCB's are only short and load protection have you limited AC input on the multi to 32Amps? and what loads do you have on the Multi and what size is the multi? So how is the multi wired AC in AC outs used and to what are they connected to? Any ET112 and how is it connected? just trying to see how its wired if you have a single line diagram can you post it as it will help you get more people to your aid @MattFR

Yes, mcbs. See attached images. The selectivity between a 32A and 40A mcbs is not sufficient to ensure only the 32A would trip. I didn't install the property electrics. I am not sure if I set the Multi to limit input to 32A, but as I can't turn it on now, I can't check. All I can say is that this didn't happen before when I turned it on. There are no loads, it happens in full function mode and charger only mode. It is the 5kVA model. What is ET112?

Looks like its on a temporary extension cord

Did you try to swap fase and neutral? Breaker trips if its swapped

Ok no worries yes MCB’s so you just have the multi and no energy meter. OP on another note I could be wrong but that looks like a 13amp cable on that input you don’t want that there if your running the device anything over 13amps.
You should be able to fire it up with just the batterie, it doesn’t need grid power for it to be programmed or the VE.config to be checked you have a MK3 for the VE as I see a cable to the VE already. What does the AC in wire go to, straight through the CU or via a 13amp plug? Just looking at it you potentially have both input and output neutral of the multiplus connected. please correct me both CU are separate?

One just on the out put of the multi and one from the input which one is which, it looks like you could cross the neutral with the work shop lights which would connect input to out put would this trigger a trip possible all I know that its a big No no if it is, the ring is another potential point unless that is a separate ring all by itself but I don’t see a change over switch so the output loads can be cut from the input. To the above what is the input cu and what is the load cu?

First things first input cable looks very undersized check cable for shorts/melting best to change cable for proper size 10mm minimum I believe the victron requirements are I could be wrong so please refer to manual the neutral earth and live look in the right positions but that cable size on the input is getting to me replace it if you can and try or get an electrician in to wire to the CU that is probably best let us know how it’s goes post back so we know too

This is a temporary lash up to get the Multi set and working with the batteries. I will use a properly sized ac input cable when wired in permanently. As the photo shows, there are no other connections than the battery and the ac in, which is connected correctly. Also, as I said the arrangement had been working previously. I must have be bad, because not only is the Multi not playing ball, but the batteries have shut down due to over voltage of some cells. But that's another story I'm taking up with SOK.

Check that cable as it’s not rated for 4kW draw it could have broken down. ideally I would put everything to do with the workshop on one board the lights won’t push you over the limit unless your still running fluorescent or the halogen lights, if all LED’s i would move to the board where the workshop is but that’s just me.

Thank you for your help. Best. Matt