Question 499Electricity & Electronics - QMED

The correct answer is A) thermal circuit breaker. A thermal circuit breaker is the best way to protect a motor from overheating due to sustained motor overload. The thermal circuit breaker monitors the current flowing through the circuit and will automatically trip and disconnect the power if the current exceeds a safe level for an extended period, preventing the motor from overheating. The other options are not as effective for this purpose. Quick-acting fuses (B) and single element fuses (D) may blow too quickly and disconnect power even during normal temporary overloads. Magnetic circuit breakers (C) respond to the instantaneous current level rather than sustained overload conditions.