Practice Test Geeks(EGSA) Electrical Generating Systems Association Certified Practice Test
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Electrical Systems Troubleshooting Flashcards

7 cards from real EGSA practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.

Read the first 7 Electrical Systems Troubleshooting flashcards as text

  1. A generator shows high AC voltage output but the frequency is correct. What is the most likely cause?

    Answer: Faulty AVR

    The Automatic Voltage Regulator (AVR) controls output voltage; a faulty AVR can cause voltage to rise above set point while frequency remains governed correctly.

  2. When troubleshooting a generator that trips on overcurrent, which test should be performed first?

    Answer: Megohmmeter test on windings

    A megohmmeter test identifies insulation breakdown in windings, which is a common cause of sustained overcurrent trips.

  3. A transfer switch fails to transfer to the emergency source after generator start. The most likely cause is:

    Answer: Faulty sensing relay in the transfer switch

    The transfer switch sensing relay monitors utility voltage loss and initiates the transfer; a faulty relay prevents the switching sequence from completing.

  4. What does a high resistance measurement across a closed circuit breaker indicate?

    Answer: Damaged or pitted contacts

    High resistance across a closed breaker indicates damaged, burned, or pitted contacts that increase contact resistance and cause voltage drop.

  5. A three-phase generator produces balanced voltage but one phase has no load current. What is the most likely fault?

    Answer: Open circuit on the load side of that phase

    Balanced voltage with zero current on one phase points to an open circuit on the load distribution side for that phase, not within the generator itself.

  6. Which instrument is used to measure insulation resistance in generator windings?

    Answer: Megohmmeter

    A megohmmeter applies high DC voltage to measure insulation resistance, identifying degradation before it causes catastrophic failure.

  7. A diesel generator hunts (surges) at no-load but stabilizes under load. The most likely cause is:

    Answer: Worn or sticking governor linkage

    Governor hunting at no-load with stabilization under load typically indicates a mechanical issue such as worn or sticking governor linkage affecting fuel control sensitivity.