Transformer Single-Phase Connections

Author: E.E. Kimberly

Transformers are sometimes provided with divided coils in both primary and secondary windings. The transformer in Fig. 17-7 has four coils connected to provide 110-volt or 220-volt service from a single-phase 2200-volt feeder. Fig. 17-8 shows the same transformer connected to provide only 110-volt service from a 1100-volt feeder, but its effective capacity is then unchanged.

Fig. 17-7. House-Lighting Transformer

Fig. 17-8. House-Lighting Transformer