I'm looking for some advice on how I would accomplish this. The idea I have is to use Multiplus to take the 120v shore power initially & step it up to 240 split phase with the AutoTransformer and then have the AutoTransformer feed a 120/240v split phase circuit break panel.
The loads are 240v 30a and the shore power in is 120v 30a North America use.
Yes, connect the AC output of a 120 volt Multi between L1 and the neutral (center tap) of the auto transformer, then L1, neutral and L2 to your load distribution panel.This is shown in data sheet: Autotransformer 32A and 100A
I checked and both Victron autotransformers are specked for 28 amps continuous neutral (center tap) current so you should be OK in your system. Because you are limited by your 30 amp input connection the 32 amp autotransformer should be sufficient.
This will certainly work. Do you not have split phase power available? If you do, you'd be putting all the load on one leg of the split phase service.
Take a look at the Multiplus II 120x2. It's designed to work with both 30 amp single leg (120 volt) service as well as 50 amp 120/240 split phase service.
At this particular location, no only 120v 20a single phase is available to me. I have been looking at that exact Multiplus, but it only outputs 240v split phase if I have that coming in, which in my case I don't.
This is the part I'm trying to figure out how to get the load to 240v if I only have single coming in. Would the AutoTransformer allow me to do that?
Do you actually have 240 volt loads? If not, you can just feed both sides of the distribution panel with the single phase. That's what a 30 amp to 50 amp dog-bone does and what the Multi II 120x2 does when inverting.
If you do have 240 volt loads then you WILL need a transformer to make 240 volts from 120 coming in.
Note that there is a limit to the amount of current on the center tap of the Victron autotransformers that is less than the VA rating suggests. Since the center tap will be used for the input side, that will limit the amount of total current you can supply even for a larger transformer.
Not all transformers have the same limitation so you might look at alternatives. Look for transformers that have dual primary and dual secondary windings. You can then wire the two input windings in parallel and the two output windings in series to get 120-0-120 on the output.
Yeah, I actually have two 240v loads—one is pulling exactly 15a & the other 10a (not being used at the same time).
And if I'm understanding correctly, I can then take the AC out from the AutoTransformer and feed the distribution panel directly with L1 & L2.
I'm looking at the 100A version of the AutoTransformer assuming the software allows me to edit the amps.
I'll take a look at what options I have with dual primary & secondary windings. That's an option I haven't considered.
