Fig. 2,140.—Diagram of transformer system with one transformer located at a distribution center and supplying several customers as A, B, and C. Such arrangement is considerably more efficient than that shown in fig. 2,139, as explained in the accompanying text.
Ans. Less transformer capacity is required than with individual transformers.
Ques. Why is this?
Ans. With several customers supplied from one transformer it is extremely improbable that all the customers will burn all their lamps at the same time. It is therefore unnecessary to install a transformer capable of operating the full load, as is necessary with individual transformers.
Ques. Does the difference in transformer capacity represent all the saving?
Ans. No; one large transformer is more efficient than a number of small transformers.
Ques. Why?
Ans. The core loss is less.