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jsjkmullin avatar image
jsjkmullin asked

Stacking two 120v Multiplus with 50amp service?

I have a sailboat with two 3k 120v Multiplus inverter/ chargers that are currently set up to provide split phase. They work just fine as set up now while on shore power or generator but I would like to stack them parallel to increase the available wattage while inverting. I am wondering if I can leave the AC input wired as if split phase but wire the output as if they are parallel to give me what I am looking for while inverting. The concern that I have is both the shore power and generator are 50amp and have L1 and L2 hot wires (220v) and the multiplus inverters do not have an input for L2. I put together what I think is a schematic that will work but would like to get thoughts before I rewire the inverters. Please don't look too much into the illustration for the ground, it is not complete. I also could be completely off base on this and what I am trying to do is not possible, so please let me know if I am. If this is not possible as depicted, would adding an isolation transformer be my next best step?carisma-wiring-schematic.jpg

multiplus in parallelmultiple invertersIsolation Tranformer
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1 Answer
derrick thomas avatar image
derrick thomas answered ·

You cannot have split phase input and parallel output. Either split phase in and out, or parallel in and out. You could add a transformer to the split phase outputs which can Ballance the loads across both phases of the input (this being the inverters outputs. Meaning, if you have say 2000 watts load on one phase of your load center, the transformer can balance that load across both phases of the inverters, essentially giving you more available power on a single phase of the load center) This however is outside my wheelhouse but I'm sure there are others on here that can tell you all about it.

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