Hi,
On my camper I have a Multiplus 2 12/3000/120 but I would avoid to use the batteries for heavy loads (hair drier etc.) when not connected to the shore.
Question: and when connected to the shore? Will the system feed directly the loads or always pass by the batteries?
What is the Passthru function?
Thanks a lot,
Ciao.
Unless your Multi is set to “Ignore AC input”, there will be a straight connection (closed relay) between input and output.
Since the Multi can’t predict what load you will connect, the easiest way to avoid powering big loads from battery would be to actually wire them to the AC IN instead of AC OUT and only connect critical / small loads to AC OUT.
Hi Bart,
sorry but I´m a little confused: does the MP ignore or not?
Big load, small load…I do not want suck the batteries, when connected, at all; should I connect a dedicated wire on the 2nd output, just for this (air drier, etc…)?
Hey,
Some of these settings can be changed in the configuration or with Node Red, but here’s the general rule:
So yes, the recommendation for your use case is to connect your heavy loads to AC OUT2.
You could connect it directly to the feed from shore power (AC IN) but if it’s connected to AC OUT2 you have the advantage that in certain conditions you can choose to power AC OUT2 from the battery as well.
This would require at least some extra software settings.
Passthru mode pretty much means that the internal charger/inverter inside the Multi is switched off and power goes directly from AC IN to AC OUT.
Hope this helps ?
Bart
Hi Bart,
yes it helps a lot, thank you.
question:
which software could I use for interact with the Multiplus II?
ciao e grazie 
Good morning,
I’m using a GX device and some Node Red voodoo
Hi all,
Another question:
The multiplus II is quite noisy overnight, so I shut it off; the problem is even connected to the shore power, all the 230V, in the camper, is not energized. If I use the 2nd output (now is not in use), is it energized even if the multiplus in shut off?
Grazie e ciao.
Hello Lapdi, would like to join the conversation, since also interested in such setup, but I’ve heard that it is not a best solution to off/on inverters on daily basis, it’s been designed for continuous work.
So is it a good idea to switch off/on inverter on regular basis?
Thanks in advance!
Unfortunately, turning the Multi off means everything connected to the output (any output) is off as well.
Are you on the latest firmware ? I believe some noise control was added in newer firmwares.
In case you want a solution where you can chose to either use the Multi in some cases and not in other cases, a transfer switch is the solution.
With that you can connect your output to either an output from the Multi, or directly to shore power.
If you’re using the Output 2 of the Multi for larger loads, you’ll need a 2nd transfer switch for those.
Or connect them to shore power, but (as stated earlier) then you’ll lose the capability to power them from the Multi, in the odd case that would be needed.
As long as you’re not turning them on and off every minute or every hour, I don’t see a reason why they can 't be turned off in the evening and back on in the morning.
That doesn’t even sound like abusive usage.
Heck, I programmed the Multi’s at my construction yard to do exactly that and none of them ever complained 
Victron stuff is well designed and can take a punch or two, probably even more
Great, thank you! So if I use transfer switch with 2 inputs, one for main and another for inverter, output to my house utilities than everything is good?
I understand that with Victron off, I have to manually switch transfer to choose source input.
@Lapdi I apologize for the some offtopic discussion but I guess we both find a solution. I am using transfer switch with one of my OEM inverter and it works quite well so I reckon it will suite your needs also, like Bart said.
A transfer switch should solve your problem, yes.
There are automatic ones and manual ones, the choice is up to you.