I purchased the Sunny Boy 5.0 in the US and shipped it out to the Philippines where I live. I have it connected to 10 500W panels on my roof and the AC is connected to a breaker I added to my house panel. During the commissioning process, you have to select the correct parameters for your grid. None of the options looked right, so I called SMA tech support. They told me that this inverter will not work on Single Phase 220v grids. She told me I would need a step-down transformer that has 2 120v lines as output in order to connect the inverter.
Does anyone have experience connecting A Sunny Boy US inverter to a single phase 220v connection? Does anyone know where I can get a stepdown converter that would work for this?
I live in the middle of nowhere, so returning the item would cost the same as getting a new one, plus the case was cracked in shipping.
Any ideas? Thanks for any help offered.
Talk to another electrician. You probably do NOT want a step down transformer. The person you spoke to may have been confused. Show another electrician the installation instructions as well as the specs. You did not include the options, but there should be one that fits.
The Sunny Boy 5.0 may be able to be configured for 208V three phase or 240V single (sometimes called split) phase. 240V and 220V are actually the same thing. You indicate from your question that you have 220V single phase on your grid (main breaker box) The 240V single phase from the inverter will work just fine. Make sure the inverter is configured for 240V NOT 208 3 phase. I believe that model can be configured for either one.
(Please include the configuration and commissioning options.)
On your Mains: Make sure what you have coming in. If you have one breaker marked 240 or 220, or if you have two 110/120V breakers ganged together, then you do indeed have 220/240 (as well as 110/120 on other breakers) and should be good. Have an electrician measure it if you are in doubt.
On the output from your inverter:
Check if there is a switch or configuration to change from 208V 3 phase to 240V single phase. I believe this model can be configured either way. You don't want 208V.
Look at the labeled output. You might have L1, L2, L3 and neutral, or just L1 and L2 and neutral, or L1 and L3 and neutral.
If you have L1 and L2 it might be for 208V. It is sometimes confusingly called 208 single phase, because it only uses those two wires, but in any case, you don't want that, so check the specs and installation manual. Better yet, measure the output. If it 208 or I think even as high as 214 it is probably configured for 208V. Double check the configuration settings.
If you have all three lines, or just L1 and L3 and neutral, then you should be able to connect without any trouble.
In any case, measure the two hot lines one to the other, and then measure each to neutral. You should get hot to hot = 240V and each hot to neutral =120V. If you do, you can wire it to the grid properly. If you are unsure how to do that, get an electrician to help, as doing it through the forums is difficult.
