Which device isolates a load from the supply while stepping down voltage?

Which device isolates a load from the supply while stepping down voltage?

• A. Transformer
• B. Fuse
• C. Switch
• D. Regulator

Answer: (A)

A transformer isolates a load from the supply while stepping down voltage. It transfers energy through magnetically coupled primary and secondary windings, so there’s no direct electrical connection between input and output, providing galvanic isolation. By selecting the turns ratio of the windings, the secondary voltage can be reduced to the desired level, achieving both isolation and voltage reduction. A fuse protects against overcurrent, but doesn’t change voltage or provide isolation. A switch simply opens or closes a circuit. A regulator can set a stable output voltage but does not provide isolation between input and output.

A transformer isolates a load from the supply while stepping down voltage. It transfers energy through magnetically coupled primary and secondary windings, so there’s no direct electrical connection between input and output, providing galvanic isolation. By selecting the turns ratio of the windings, the secondary voltage can be reduced to the desired level, achieving both isolation and voltage reduction. A fuse protects against overcurrent, but doesn’t change voltage or provide isolation. A switch simply opens or closes a circuit. A regulator can set a stable output voltage but does not provide isolation between input and output.