EGSA Generator Set Maintenance 2

Question 1

When performing a load bank test on a standby generator, what minimum load level is typically recommended to prevent wet stacking?

Accepted Answer

75% of rated capacity

Answer

Load bank testing at 75% or more of rated capacity burns off carbon deposits and unburned fuel that cause wet stacking in lightly loaded diesel engines.

Question 2

Which maintenance task is most critical before storing a generator set for an extended period of more than 6 months?

Accepted Answer

Fogging the engine cylinders with preservation oil

Answer

Fogging cylinders with preservation oil prevents rust and corrosion on cylinder walls and piston rings during long-term storage.

Question 3

A generator's voltage regulator is replaced but the output voltage still fluctuates. What is the most likely next component to inspect?

Accepted Answer

Alternator brushes and slip rings

Answer

Worn or contaminated brushes and slip rings cause irregular contact, producing voltage fluctuation even with a new AVR installed.

Question 4

What does a rising trend in crankcase pressure readings during routine maintenance indicate?

Accepted Answer

Worn piston rings or cylinder liners allowing blow-by

Answer

Elevated crankcase pressure indicates combustion gases are bypassing worn piston rings into the crankcase, a sign of internal engine wear.

Question 5

During a maintenance inspection, technician finds white crystalline deposits around coolant hose fittings. What does this indicate?

Accepted Answer

Slow coolant leak allowing deposits to form as coolant evaporates

Answer

White crystalline deposits around fittings are a classic sign of a slow coolant leak where the liquid evaporates and leaves mineral residue behind.

(EGSA) Electrical Generating Systems Association Certified Practice Test

(EGSA) Electrical Generating Systems Association Certified Practice Test

EGSA Generator Set Maintenance 2