substation

A subsidiary or branch station, as of a post office or an electric utility.

A subordinate station: as, a police substation.

A subsidiary station to supplement a main station.

A site where electricity supplied by long-distance (high-voltage) transmission lines is transformed and/or regulated for local (low-voltage) distribution.

A satellite police station serving one neighborhood or part of a larger jurisdiction.

a subsidiary station where electricity is transformed for distribution by a low-voltage network