In distribution stations, what equipment steps down 34.5 kV to 4.8 kV?

• A. Transformers
• B. Switchgear
• C. Circuit breakers
• D. Reactors

Answer: (A)

The main idea is that a transformer is used to change voltage levels in a distribution station. A step-down transformer takes the high voltage on the primary side, 34.5 kV, and converts it to the lower distribution voltage, 4.8 kV, using a turns ratio. This is how the system delivers usable voltage to customers while keeping power flow efficient. The transformer operates on electromagnetic induction, so the voltage ratio equals the turns ratio, and the power stays nearly the same (neglecting losses), meaning the current on the 4.8 kV side is higher than on the 34.5 kV side by the same factor.

Switchgear, circuit breakers, and reactors don’t change voltage levels. Switchgear houses switches and protection equipment to route and isolate circuits. Circuit breakers interrupt current during faults or during switching. Reactors mainly control reactive power or limit fault currents. None of these steps down voltage like a transformer does, which is why a transformer is the correct choice for stepping 34.5 kV down to 4.8 kV.