The autotransformer: for balancing the increase, decrease and splitting of the phase:
An autotransformer can be used for the purposes of stepping up, stepping down and balancing the split phase output. While the step-up and step-down functions are relatively simple, balancing the split-phase output may require more attention.
Temperature protection:
In the event of overheating, the autotransformer is disconnected from the power supply. Reset is manual.