WTT Troubleshooting and Maintenance 2 — Questions and Answers
Question 1: A wind turbine's vibration sensor triggers an alarm. What is the FIRST step a technician should take?
- Immediately shut down the turbine and climb to inspect
- Review the SCADA data to identify which component shows abnormal vibration (Correct answer)
- Reset the alarm remotely and monitor for recurrence
- Replace the vibration sensor as it may be faulty
Correct answer: Review the SCADA data to identify which component shows abnormal vibration
Reviewing SCADA data first helps localize the vibration source before any physical inspection or shutdown decision.
Question 2: Which lubricant property is most critical when selecting grease for a main bearing operating in cold climates?
- High viscosity index
- Low pour point (Correct answer)
- High dropping point
- Water resistance rating
Correct answer: Low pour point
A low pour point ensures the grease remains pumpable and does not solidify at low ambient temperatures.
Question 3: A technician finds oil contamination in the gearbox breather vent. What does this most likely indicate?
- Normal breathing during thermal cycling
- Overfilling of gearbox oil beyond the maximum level (Correct answer)
- A blocked oil return line causing pressure buildup
- Incorrect oil viscosity grade installed
Correct answer: Overfilling of gearbox oil beyond the maximum level
Overfilling the gearbox raises the oil level above the breather port, causing oil to be expelled during operation.
Question 4: During a scheduled inspection, a technician notices pitting on the surface of a gear tooth. This defect is classified as:
- Spalling
- Scoring
- Micropitting (Correct answer)
- Abrasion
Correct answer: Micropitting
Micropitting appears as fine pits or frosted surfaces on gear teeth caused by surface fatigue under elasto-hydrodynamic lubrication conditions.
Question 5: When troubleshooting an intermittent pitch control fault, which tool provides the most useful real-time diagnostic information?
- Infrared thermometer
- SCADA trend logging (Correct answer)
- Dial caliper
- Ultrasonic thickness gauge
Correct answer: SCADA trend logging
SCADA trend logging captures timestamped data that helps correlate pitch faults with wind speed, temperature, and other operational parameters.
Question 6: A generator bearing temperature reading is 15°C above its normal operating range but below the shutdown threshold. What is the correct action?
- Continue operation and log the reading for trend analysis
- Increase lubrication frequency and schedule an inspection at the next opportunity (Correct answer)
- Immediately shut down the turbine to prevent damage
- Reduce turbine output by 50% and continue monitoring
Correct answer: Increase lubrication frequency and schedule an inspection at the next opportunity
An elevated but sub-threshold bearing temperature warrants increased lubrication and a prompt planned inspection rather than an unscheduled emergency shutdown.
Question 7: What is the primary purpose of performing an oil particle count analysis on gearbox oil?
- To verify the oil viscosity grade meets specifications
- To detect early-stage wear before catastrophic failure occurs (Correct answer)
- To confirm the oil change interval has been met
- To measure water content in the lubricant
Correct answer: To detect early-stage wear before catastrophic failure occurs
Particle count analysis identifies metallic wear debris in the oil, enabling early detection of component degradation before failure occurs.
WTT Troubleshooting and Maintenance 2
A wind turbine's vibration sensor triggers an alarm.
What is the FIRST step a technician should take?