What safety mechanism can prevent accidental operation of a motor?

The emergency stop button is a critical safety mechanism designed to halt the operation of a motor in the event of an emergency or hazardous situation. It provides a quick, easily accessible way for operators to disconnect power to the motor immediately, thus preventing accidental operation or potential injury. This button is typically prominently marked and located where operators can reach it without delay.

In contrast, while a speed regulator controls the speed of the motor and an overload relay protects the motor from damage due to excessive current, neither of these directly prevents the motor from being accidentally turned on. Similarly, a voltage stabilizer helps maintain a consistent voltage level to the motor, ensuring its reliable performance but does not offer a means of stopping operation. Thus, the emergency stop button stands out as the most effective solution for preventing accidental motor operation.