Aux 1 Unit 4 Q4

Correct Answer: B) Frequent tripping of circuit breakers

Explanation: Frequent tripping of circuit breakers is an indication of electrical faults, such as short circuits, overloads, or insulation failures within the motor or associated wiring.

Correct Answer: B) Bearing failure or lack of lubrication

Explanation: Excessive heat in the motor can be caused by bearing failure or lack of lubrication. When bearings fail or are not properly lubricated, they generate more friction, leading to overheating.

Correct Answer: B) Unusual noise or vibration coming from the pump or motor

Explanation: Unusual noise or vibration is a common indication of a fault in a pump/motor set. It could signal mechanical issues such as misalignment, bearing failure, or impeller damage.

Correct Answer: B) Excessive heat generated by the motor

Explanation: Excessive heat in the motor is a sign of a fault, which could be due to overloading, bearing failure, or poor ventilation. Overheating can damage the motor if not addressed promptly.

Correct Answer: A) Impeller wear or damage

Explanation: Impeller wear or damage reduces the pump's ability to generate the necessary pressure, leading to a sudden drop in discharge pressure. This could also result from cavitation, where vapor bubbles damage the impeller.

Correct Answer: B) Misalignment or wear of the seals

Explanation: Persistent leaks at the pump seals are often caused by misalignment or wear. Over time, seals can degrade, or if not properly aligned, they may not provide an adequate seal, resulting in leaks.

Correct Answer: C) A fault such as seal wear or misalignment

Explanation: Persistent leaks at the pump seals usually indicate that the seals are worn or that there is a misalignment causing improper sealing. This can lead to fluid loss and reduced efficiency.

Correct Answer: C) A fault such as impeller wear or cavitation

Explanation: A sudden drop in discharge pressure can indicate that the pump's impeller is worn or that cavitation is occurring, both of which would reduce the pump's ability to maintain proper pressure.

Correct Answer: B) Electrical short circuit or motor overload

Explanation: Frequent tripping of circuit breakers is typically caused by electrical short circuits or motor overloads. This could indicate issues such as insulation breakdown, incorrect wiring, or an overloaded motor.

Correct Answer: B) Misalignment of the pump and motor shafts

Explanation: Misalignment between the pump and motor shafts is a common cause of unusual noise or vibration. This misalignment puts additional stress on the bearings and other components, leading to noise and potential damage.