What is an example of a power-passing device?

A power-passing device is one that allows electrical power to pass through it while functioning in a control or switching capacity. The fan switch serves as an excellent example of this type of device because it directly regulates power to the fan motor in order to control its operation. When the switch is closed, it permits electrical current to flow to the fan, enabling it to run. When opened, it interrupts the flow of current, effectively turning the fan off.

In contrast, a thermostat primarily serves to detect temperature and provide control signals rather than directly manage the flow of electricity for a fan. A voltage regulator is designed to maintain a constant output voltage rather than passing power for operational control. Meanwhile, a current monitor tracks the current flowing through a circuit but does not facilitate the passage of power for operational control like the fan switch does. Therefore, the fan switch is the most appropriate example of a power-passing device in this context.