MCQs

Which one of the following is classified as an electrical fault: Loss of boiler firing Over speeding Excessive vibration Loss of synchronism Correct answer: 4. Loss of synchronism

The most common cause of motor damage is: Faulty protection Rotor fault Insulation fault Overheating due to long time running Correct answer: 3. Insulation fault

Active fault refers to: Phase to Phase faults Phase to Earth faults Both of these None of these Correct answer: 3. Both of these

The term Passive faults in Power system refers to: Overvoltage Under frequency Power swings All of these None of these Correct answer: 4. All of these The term Passive fault refers to the faults that are not actual faults but the conditions that are stressing the electrical system. All overvoltage, under frequency, overloading, and power … Read more

Incipient faults are best defined as faults that: Cause immediate breakdown Cause break down after a couple of seconds Start as small and develop into dangerous failure None of these Correct answer: 3. Start as small and develop into dangerous failure

The more accurately the fault is detected by protection system, the more _______ is it: Selective Sensitive Fast Dependable Correct answer: 1. Selective

The smaller the current a protection system detects, the more the is it: Selective Sensitive Fast Dependable Correct answer: 2. Sensitive

Which type of fault has the highest probability of occurrence on the power system: L-G L-L L-L-G L-L-L Correct answer: L-G Explanation: The L-G fault has highest probability of occurrence on power system

The most severe fault on power system: L-G L-L L-L-G L-L-L Correct answer: L-L-L The line to line to line or L-L-L fault is most severe type of fault electric power system

Shunt faults are also known as: Open circuits Short circuits Phase to Neutral Faults None of these Correct answer: 2. Short circuits