CO Wind Turbine Technician
Contractor Exam Practice Questions
And Correct Answers (Verified
Answers) Plus Rationale 2027 Q&A|
Instant Download Pdf.
1. A wind turbine technician is preparing to perform maintenance
inside the nacelle. Before beginning work, which action is most
important for preventing unexpected turbine startup?
A. Increase the blade pitch angle manually
B. Disconnect only the control-room communication system
C. Apply lockout/tagout to all relevant energy sources and verify zero-
energy state
D. Lower the hydraulic system pressure by opening one service valve
Correct Answer: C
Rationale: Lockout/tagout procedures isolate hazardous electrical,
mechanical, hydraulic, pneumatic, and other energy sources and require
verification that the equipment cannot unexpectedly start before
maintenance begins.
, 2. What is the primary function of a wind turbine gearbox in a
conventional geared wind turbine?
A. To reduce generator voltage before transmission
B. To increase the relatively low rotational speed of the rotor to a speed
suitable for the generator
C. To convert DC electricity into AC electricity
D. To maintain constant hydraulic pressure in the pitch system
Correct Answer: B
Rationale: The rotor turns relatively slowly, while many generators
require substantially higher rotational speeds, so the gearbox increases
rotational speed between the low-speed shaft and generator.
3. Before climbing a wind turbine tower, a technician should inspect
fall-protection equipment primarily to ensure that:
A. The harness color matches the site safety program
B. All components are free from damage, excessive wear, and defects that
could impair performance
C. The lanyard is longer than the tower ladder
D. The harness has been stored in the nacelle for at least 24 hours
Correct Answer: B
Rationale: Harnesses, lanyards, connectors, and other fall-protection
components must be inspected for cuts, abrasion, corrosion,
deformation, and other defects before use.
, 4. Which wind turbine component is primarily responsible for
converting the aerodynamic energy of moving air into rotational
mechanical energy?
A. Transformer
B. Rotor blades
C. Power converter
D. Main controller
Correct Answer: B
Rationale: Rotor blades are aerodynamically shaped to capture energy
from the wind and produce rotational torque that drives the turbine
drivetrain.
5. A technician observes excessive vibration in a wind turbine
drivetrain. Which condition is a likely potential cause?
A. Proper shaft alignment and balanced rotating components
B. Worn bearings or misalignment of rotating equipment
C. Correct lubrication levels and normal gear mesh
D. Properly tightened electrical terminal connections
Correct Answer: B
Rationale: Bearing deterioration, shaft misalignment, imbalance, and
drivetrain defects can create abnormal vibration and should be
investigated before significant equipment damage occurs.
6. What is the primary purpose of a wind turbine yaw system?
, A. To regulate generator voltage
B. To rotate the nacelle so the rotor faces the wind appropriately
C. To change the blade airfoil shape
D. To cool the gearbox lubricant
Correct Answer: B
Rationale: The yaw system positions the nacelle and rotor relative to
changing wind direction so that the turbine can capture wind energy
efficiently.
7. Why is verification of absence of voltage necessary after electrical
isolation?
A. Because opening a disconnect always guarantees that conductors are
de-energized
B. Because stored energy, incorrect isolation, or equipment faults may
leave hazardous voltage present
C. Because electrical equipment cannot be grounded until voltage is
detected
D. Because generators cannot produce electricity during maintenance
Correct Answer: B
Rationale: Technicians must verify that hazardous voltage is absent
because disconnecting equipment alone does not guarantee complete
de-energization or elimination of stored electrical energy.
8. What is the principal function of the pitch control system?
Contractor Exam Practice Questions
And Correct Answers (Verified
Answers) Plus Rationale 2027 Q&A|
Instant Download Pdf.
1. A wind turbine technician is preparing to perform maintenance
inside the nacelle. Before beginning work, which action is most
important for preventing unexpected turbine startup?
A. Increase the blade pitch angle manually
B. Disconnect only the control-room communication system
C. Apply lockout/tagout to all relevant energy sources and verify zero-
energy state
D. Lower the hydraulic system pressure by opening one service valve
Correct Answer: C
Rationale: Lockout/tagout procedures isolate hazardous electrical,
mechanical, hydraulic, pneumatic, and other energy sources and require
verification that the equipment cannot unexpectedly start before
maintenance begins.
, 2. What is the primary function of a wind turbine gearbox in a
conventional geared wind turbine?
A. To reduce generator voltage before transmission
B. To increase the relatively low rotational speed of the rotor to a speed
suitable for the generator
C. To convert DC electricity into AC electricity
D. To maintain constant hydraulic pressure in the pitch system
Correct Answer: B
Rationale: The rotor turns relatively slowly, while many generators
require substantially higher rotational speeds, so the gearbox increases
rotational speed between the low-speed shaft and generator.
3. Before climbing a wind turbine tower, a technician should inspect
fall-protection equipment primarily to ensure that:
A. The harness color matches the site safety program
B. All components are free from damage, excessive wear, and defects that
could impair performance
C. The lanyard is longer than the tower ladder
D. The harness has been stored in the nacelle for at least 24 hours
Correct Answer: B
Rationale: Harnesses, lanyards, connectors, and other fall-protection
components must be inspected for cuts, abrasion, corrosion,
deformation, and other defects before use.
, 4. Which wind turbine component is primarily responsible for
converting the aerodynamic energy of moving air into rotational
mechanical energy?
A. Transformer
B. Rotor blades
C. Power converter
D. Main controller
Correct Answer: B
Rationale: Rotor blades are aerodynamically shaped to capture energy
from the wind and produce rotational torque that drives the turbine
drivetrain.
5. A technician observes excessive vibration in a wind turbine
drivetrain. Which condition is a likely potential cause?
A. Proper shaft alignment and balanced rotating components
B. Worn bearings or misalignment of rotating equipment
C. Correct lubrication levels and normal gear mesh
D. Properly tightened electrical terminal connections
Correct Answer: B
Rationale: Bearing deterioration, shaft misalignment, imbalance, and
drivetrain defects can create abnormal vibration and should be
investigated before significant equipment damage occurs.
6. What is the primary purpose of a wind turbine yaw system?
, A. To regulate generator voltage
B. To rotate the nacelle so the rotor faces the wind appropriately
C. To change the blade airfoil shape
D. To cool the gearbox lubricant
Correct Answer: B
Rationale: The yaw system positions the nacelle and rotor relative to
changing wind direction so that the turbine can capture wind energy
efficiently.
7. Why is verification of absence of voltage necessary after electrical
isolation?
A. Because opening a disconnect always guarantees that conductors are
de-energized
B. Because stored energy, incorrect isolation, or equipment faults may
leave hazardous voltage present
C. Because electrical equipment cannot be grounded until voltage is
detected
D. Because generators cannot produce electricity during maintenance
Correct Answer: B
Rationale: Technicians must verify that hazardous voltage is absent
because disconnecting equipment alone does not guarantee complete
de-energization or elimination of stored electrical energy.
8. What is the principal function of the pitch control system?
