Victron Autotransformer - Split Phase 120/240V - 100AMP [ITR000100101]Autotransformer Split Phase 120 240V 100AMP The Autotransformer: for step up, step down and split phase balancing An autotransformer can be used for step up, step down and split phase output balancing purposes. While the step up and step down functions are fairly straightforward, split phase output balancing may require some more attention. Consider for example a 30A 120 240V split phase supply. The supply could be the grid, a generator or two stacked