I am considering 2 MultiPlus-II 12/3000/120-50 2x120V models. I need to support 5.5kw 220 at 29amp and am not sure if a transformer is necessary (https://www.victronenergy.com/upload/documents/Datasheet-Autotransformer-32A-and-100A-EN.pdf) or if I could stack the two 120v inverters to support both 120 and 220 loads simultaneously . Your advice is greatly appreciated,
Superbedankt!
Ty for any response! :beer:
Any suggestions, comments, criticisms?
How would you run support for both 120v and 220v appliances?
You can run stacked inverters to support 120 and 240 volt loads. However you will only get the full power output of both if the 120v loads are perfectly balanced between the two 120v legs.
Adding an autotransformer allows you to automatically balance the loads between the two inverters regardless of how they're distributed in the panel. The "stacked inverter balancing" diagram in the autotransformer PDF shows this configuration.
Disclaimer: I'm not any kind of a professional at this, just an interested hobbyist.
@TK-421 thank you for pointing out that diagram in my own link - ha - missed it. Seems possible then in my mind with a 12v battery bank and dual inverters. Well, at least seems promising. Still searching for confirmation if this is the best strategy.
Stacked Multis, yes but not the 2x120. It has internal logic to manage 120/240 incoming that would be confused by stacking I think.
If you need to power 240v ac appliances, you would be better off just using two Multis or MPII 1X120 models as that is what the MPII will turn into when configuring in split phase.
