The day is coming where people will begin to discard non-working solar inverters. May of them have a honking big toroidal transformer. Does anyone know what is the typical inverter side voltage of these transformers is? Next step is to think of a project using one. 
Hi
273.8328 VA at 281.68962 uH using a material that is optimum at 73.892 KHz

There are roughly a zillion different designs for these gizmos out there. They run to a wide variety of output voltages and loads. The inductors in them are going to be all over the place. Simple answer is to pull it off the board, measure it, and see what you have.
Bob