The new transformer design used an ungapped pot core that was less costly and easier to obtain than a gapped pot core.

The required VA ratings of auto-couple transformers is much less than its output power, thus the size and price of the transformer is reduced a lot.

Terminal Transformer Unit (TTU) is an important portion of Distribution Automation. But most TTU products have some disadvantages like costly price, few functions, lack of compatibility, and so on.