A 21,000-kv-a. automatic substation

The present practise in the design of distribution substations shows a tendency towards the more extensive use of automatically controlled equipment to replace the older manually-operated type. This paper is of interest therefore as an example of the type of equipment used by one company, and also for some of the reasons why this type was decided upon. The paper includes a summary of the apparatus and control equipment, general scheme of operation, together with floor plans of the building, one-line diagrams illustrating the operation, and a view of a portion of the single-phase regulator equipment. It also includes a summary showing the total kv-a. capacity of apparatus that is automatically controlled.