Final answer:
The electrical motor protection device that automatically resets itself is the circuit breaker. It acts like an automatic switch, opens when the current exceeds limits, and can be reset after tripping.
Step-by-step explanation:
The electrical motor protection device that automatically resets itself is the circuit breaker.
A circuit breaker is a device that acts like an automatic switch and opens when the sustained current exceeds desired limits. It is designed to protect the motor and other electrical equipment from overloading or short-circuiting.
Unlike fuses, circuit breakers can be reset after they trip. Once the fault or overload is corrected, you can simply switch the breaker back on to restore the power.