Question 503Electricity & Electronics - QMED

The correct answer is B) The breaker cannot be reset to the ON position until the thermal element cools down. When a molded-case circuit breaker with a thermal trip unit trips due to an overloaded motor circuit, the thermal element heats up and trips the breaker. After the trip, the thermal element needs to cool down before the breaker can be reset and returned to the ON position. This is a safety feature to prevent the breaker from being reset too soon, which could lead to further damage to the overloaded circuit. The other answer choices are incorrect because the breaker handle does not lock in the OFF or TRIPPED position, and the thermal element does not need to be replaced after a trip unless it is damaged.