33 kv sub station

one or two incoming feeders. few isolators ( air Break Switches), Few circuit breakers, Transformers one ,2 or more. Bus bar conductors, Structures, Line accessories, earth pits, earthing strip, bus duct or cable , secondary in ccoming breaker and out going panels, bolts nuts etc etc.did u ask this seriously?

Good answer.

Depending on whether the equipment is indoor or outdoor rated, you may want to include walls, roof, lighting, HVAC, etc.

There is need for you to be specific on the subject matter, injection s/s, transmission s/s, manned substation or unmanned substation .

Dangambo Hussaini