Question 499Electricity/Electronics - QMED70% to pass
How can a motor be protected from overheating due to sustained motor overload?
AI Explanation
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.
Related Questions
#497 How does a circuit breaker differ from a fuse? #498 By what means is protection against sustained overloads occurring in molded-case circuit breakers provided? #500 A thermal-magnetic circuit breaker for a 300 kW alternator is rated at 500 amperes at full continuous load. Which of the following conditions will trip the breaker? #501 When the operating handle of a molded-case circuit breaker is in the mid-position, what is the indication for the position of the circuit breaker? #502 Undervoltage trips are frequently installed on switchboard circuit breakers for what reason?