Which component supplies power to operate a low-voltage switching system?

• A. A relay
• B. A circuit breaker
• C. A transformer
• D. A capacitor

Answer: (C)

The correct choice is the transformer because it is specifically designed to change voltage levels in an electrical circuit, making it suitable for supplying power to low-voltage systems. In low-voltage switching applications, transformers step down higher power voltages to lower, usable levels. This capability allows the transformer to provide the necessary voltage and current required for the operation of such systems, ensuring that they function effectively and safely.

In contrast, while relays are crucial for controlling circuits and switching operations, they do not supply power themselves; instead, they are actuated by an existing power source. Circuit breakers serve the purpose of interrupting the flow of electricity for safety, protecting the system from overloads or faults, but they don’t provide power. Capacitors, although used in circuits to store and release energy, do not supply steady power in the same way a transformer does; their main purpose is more aligned with filtering or stabilizing voltage rather than supplying it continuously.