Enclosed Sub Station

Enclosed sub-station, means any premises or en-closure or part thereof, being large enough to admit the entrance of a person after the apparatus therein is in position, containing apparatus for trans-forming or converting energy to or from a voltage at or above medium voltage (other than trans-forming or converting solely for the operation of switchgear or instruments) with or without any other apparatus for switching, controlling or otherwise regulating the energy, and includes the apparatus therein. [Indian Electricity Rules, 1956, R. 2 (1) (t)]