Which safety device stops the elevator car if it exceeds a certain speed during descent?

• A. Overload switch
• B. Safety governor
• C. Control circuit
• D. Brake system

Answer: (B)

The safety governor is a crucial safety device in elevator systems designed to monitor and control the speed of the elevator car. When the elevator descends, the governor continuously measures its speed. If the car exceeds a specified speed—indicating an unsafe condition—the safety governor activates a mechanism that engages the elevator's brake system to halt the descent quickly and safely. This ensures that the elevator operates within its designed speed limits and minimizes the risk of accidents due to excessive speed.

The other options serve different functions: the overload switch is designed to prevent operation when the car is carrying more weight than it can safely handle, the control circuit is integral in managing the elevator's operation and logic, while the brake system is responsible for stopping and holding the elevator in place but does not monitor speed independently. Therefore, the specific role of the safety governor in regulating descent speed makes it the correct answer.