2A652 Vol 3 CDC Ure 2015

100 Questions | Total Attempts: 56

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2A652 Quizzes & Trivia

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Questions and Answers
  • 1. 
    To change electrical energy to mechanical energy is the purpose of a
    • A. 

      Generator.

    • B. 

      Converter.

    • C. 

      Inverter.

    • D. 

      Motor.

  • 2. 
    Electrical contact between the stationary and rotating parts of a motor is the function of the 
    • A. 

      Field windings.

    • B. 

      Commutator.

    • C. 

      Bearings.

    • D. 

      Brushes.

  • 3. 
    Torque is defined as
    • A. 

      Wattage.

    • B. 

      Horsepower.

    • C. 

      Rotational force.

    • D. 

      Opposition to applied voltage.

  • 4. 
    In a series-wound direct current (DC) motor, speed is dependent on the
    • A. 

      Load.

    • B. 

      Torque.

    • C. 

      Armature.

    • D. 

      Field winding.

  • 5. 
    The relationship between slip and torque can best be described as more
    • A. 

      Torque causing more slip.

    • B. 

      Slip causing more torque.

    • C. 

      Torque causing less slip.

    • D. 

      Slip causing less torque.

  • 6. 
    The three-phase induction motor does not require
    • A. 

      Slip.

    • B. 

      A rotor.

    • C. 

      A stator.

    • D. 

      A starting device.

  • 7. 
    To reverse the direction of rotation of a three-phase inductive motor, you must reverse
    • A. 

      All three phases.

    • B. 

      Any two power leads.

    • C. 

      A and B phases only.

    • D. 

      B and C phases only.

  • 8. 
    The stator windings of a synchronous motor are spaced
    • A. 

      20 degrees apart.

    • B. 

      30 degrees apart.

    • C. 

      90 degrees apart.

    • D. 

      120 degrees apart.

  • 9. 
    The rotation speed of a synchronous motor is controlled by the
    • A. 

      Load.

    • B. 

      Torque.

    • C. 

      Input frequency.

    • D. 

      Armature current.

  • 10. 
    During an inspection of a direct current (DC) motor, check the brushes for
    • A. 

      Pitting.

    • B. 

      Seating.

    • C. 

      Coloration.

    • D. 

      Brittleness.

  • 11. 
    When you check the concentricity of a commutator or slip rings, look for
    • A. 

      Wear.

    • B. 

      Pitting.

    • C. 

      Roundness.

    • D. 

      Overheating.

  • 12. 
    When using a troubleshooting chart, what are you not likely to find?
    • A. 

      Analysis.

    • B. 

      Remedies.

    • C. 

      Symptoms.

    • D. 

      Probable causes.

  • 13. 
    Most troubleshooting on a motor can be done using a
    • A. 

      Megger.

    • B. 

      Growler.

    • C. 

      Multimeter.

    • D. 

      Clamp-on ammeter.

  • 14. 
    Perform an operational check of the unit
    • A. 

      At the last minute.

    • B. 

      With the defective part removed.

    • C. 

      Before final reassembly of the enclosure.

    • D. 

      As soon as you replace the defective part.

  • 15. 
    The component most likely to be damaged by poorly filtered fuel is the
    • A. 

      Combustion chamber.

    • B. 

      Transfer pump.

    • C. 

      Fuel lines.

    • D. 

      Injectors.

  • 16. 
    The type of injector that is operated by a rocker arm is
    • A. 

      Spray.

    • B. 

      Pintle.

    • C. 

      Pressure.

    • D. 

      Mechanical.

  • 17. 
    Aside from idle speed, the limiting speed governor through the use of flyweights and spring tension controls
    • A. 

      Load speed.

    • B. 

      Minimum speed.

    • C. 

      Maximum speed.

    • D. 

      Intermediate speed.

  • 18. 
    A lubricant performs which function when it deposits particles of dirt in the oil sump?
    • A. 

      Cooling.

    • B. 

      Sealing.

    • C. 

      Cleaning.

    • D. 

      Reducing friction.

  • 19. 
    What component holds a large amount of coolant in close contact with a large volume of air?
    • A. 

      Radiator cap.

    • B. 

      Thermostat.

    • C. 

      Water pump.

    • D. 

      Radiator.

  • 20. 
    Which liquid cooling system component circulates the coolant?
    • A. 

      Vacuum valve.

    • B. 

      Water pump.

    • C. 

      Cooling fan.

    • D. 

      Radiator.

  • 21. 
    One of the impellers within a blower on a diesel engine is normally driven
    • A. 

      By the engine electrical system through a DC motor.

    • B. 

      By the engine exhaust gases flowing across the turbine wheel.

    • C. 

      From the engine crankshaft through a system of gears or a silent chain.

    • D. 

      Through a solid shaft connected between the blower and the transmission.

  • 22. 
    What must be accomplished to supercharge a diesel engine?
    • A. 

      Change the overlap and timing so that the intake and exhaust valves are not open at the same time.

    • B. 

      Change the overlap and timing so that the intake and exhaust valves are open at the same time.

    • C. 

      Advance exhaust valve opening time.

    • D. 

      Retard intake valve opening time.

  • 23. 
    The filtration step protects the diesel engine fuel system from
    • A. 

      Blockage of airflow.

    • B. 

      Lube system malfunctions.

    • C. 

      Slipping belts on the blower.

    • D. 

      Abrasion by foreign particles.

  • 24. 
    The best step in preventing abnormal amounts of carbon, moisture, and sludge buildup in a diesel engine, is to
    • A. 

      Avoid operating the engine for extended periods at no-load.

    • B. 

      Operate the unit at idle speed for long periods of time.

    • C. 

      Drain moisture from fuel system periodically.

    • D. 

      Perform a preoperational check.

  • 25. 
    When performing a compression test, measuring pounds per square inch (psi), the maximum allowable deviation between cylinders is
    • A. 

      25 psi.

    • B. 

      50 psi.

    • C. 

      75 psi.

    • D. 

      100 psi.