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1. Which of the following electrical which employs a stationary armature and a rotating electromagnetic field is used aboard ship?


2. Which of the following semiconductor that decrease in resistance with an increase in temperature?


3. What will happen if on a DC shunt motor connections are changed and either the field connections, or the armature connections are reversed?


4. Which of the following statement is correct regarding a small electrical motor that has been submerged in saltwater?


5. How will you be able to obtain the degree of control over the speed of a slip ring induction motor?


6. Which of the following will prevent a generator from becoming motorized?


7. What do you called a current flowing in one direction?


8. The instantaneous reduction in voltage of an AC generator, resulting from an increase in load, and prior to the automatic voltage regulator correcting is called.


9. The total power used in a series circuit is_______.


10. Electric current is flow of electrons through a conductor. The rate of this flow is measured in __.


11. How should a shunt used in an ammeter should be connected?


12. What do you called a direct current passing through a wire coiled around a soft iron core?


13. When a 10 HP DC motor has been started and running normally, the additional load on a DC generator will increase by approximately_.


14. Which of the following is the method used to produce emission in most vacuum, tubes?


15. A single phase induction motor starts, comes up to about 75% rated speed, slows down to a lower speed, and accelerates again. What could be the problem?


16. Which of the following regulates the output voltage of a three-phase alternator?


17. Which of the instruments can be best used to locate a grounded field coil in a synchronous motor?


18. Which of the following is the most effective in cleaning a commutator in good physical condition?


19. Which of the following is the primary function of an electric motor?


20. A limit switch is a piece of electrical apparatus to shut off a circuit which of the following statements is correct as to when the limit switch activates?


21. When troubleshooting motor controllers, a shorted relay or contactor coil is often indicated by ______.


22. Which of the following devices required in a switchboard for an AC electrical system?


23. Which of the following actions should be the final step when paralleling two DC generators?


24. Which of the following maintained the constant output voltage from an AC generator?


25. When the current in a power transmission line is increased, the power loss ___.


26. Which of the following determines the frequency of an alternator?


27. Periodic testing of circuit breakers is necessary to ensure that a correctly rated and property installed unit ___.


28. What do you called the rated temperature rise of an electric motor?


29. Which of the following is the function of the voltage regulators used with AC generators?


30. Which of the following meters uses a shunt connected in series with the load, but parallel with the movement?


31. The function of an automatic voltage regulators provided on switchboards is to_.


32. Which of the listed condition indicates on a switchboard, if all three ground detection lams remain burning at half intensity when test button is pressed?


33. The type of feature afforded auxiliaries vital to the operation of propelling equipment, where automatic restart after a voltage failure would not create a hazard, is termed__.


34. If all three ground detection lamps burn at full intensity when the best button is depressed, which of the listed condition will be indicated?


35. Which of the following statements concerning electrical cables is correct?


36. A ground is indicated by the ground-detecting system on the main electrical switchboard. The FIRST step in locating the actual ground is to _.


37. The electrolyte in a lead-acid storage battery consist of water and ____.


38. A fuse will blow for all the listed reasons except, _______.


39. A bus disconnect link is used to isolate___.


40. A silicon controlled rectifier (SCR) is a solid state device used to change _____.


41. All of the following items can be used in the maintenance of a DC motors commutator EXCEPT_______.


42. Operational amplifiers, used primarily in analog circuits, are characterized by ____.


43. The charge of a lead acid battery is checked with a/an________.


44. When starting a DC motor, where speed is controlled by a variable rheostat, the rheostat must FIRST be turned ________.


45. Low voltage releases as used in some shipboard motor starter and control equipment will have which of the following characteristics?


46. The timer element of a reverse power relay cannot be energized unless___.


47. Power transformer are rated in ______.


48. When replacing fuses, always make sure_______.


49. An important factor in reducing D.C. motor commutator wear is__.


50. One must avoid touching the bright copper surface a freshly ground D.C. motor commutator because ___.


51. In a three-phase, squirrel-cage induction motor, the rotating magnetic field is established by the___.


52. In a cartridge-type fuse, the metal element is contained in a___.


53. When charging lead acid batteries, you should reduce the charging rate as the battery nears its full charge capacity to ___________.


54. When insulation failure produces a low resistance current path between conductors, the resulting condition is known as___.


55. If a three-phase induction motor malfunctions and drops to a single-phase ( one supply line open)_______.


56. A compound motor with just one or two series field turns is called a _________.


57. It is an electric device that receives the signal from the bridge then transmits the same signal to the hydraulic pump of the steering gear system.


58. The machine that cannot be started the control room in an automated vessel is the:


59. Which of the following motors is fitted with an instantaneous overload relay?


60. Which of the following statements is correct to determine the need of cleaning the insulation?


61. How do you correct a loss of or weak residual magnetism in an alternator or generator?


62. The source of energy that opens an automatic air circuit breaker on the main switchboard is ___.


63. Which of the following electrical device is normally used to prevent an action from occurring until all other required conditions are met?


64. Which of the following is the function of a shading coil used in an AC magnetic controller?


65. Which of the following electric properties listed will always be the same for each component in a parallel circuit?


66. Which of the following is the function of automatic voltage regulators provide at the switchboards?


67. Which of the following statement is correct in measuring the voltage across a load?


68. Which of the following statement is correct if the excitation is increased to one of two alternators operating in parallel?


69. Which of the following represents a characteristic of an ungrounded electrical distribution system?


70. Which of the following procedures should be carried out to prevent moisture damage to electrical apparatus during extended periods of idleness?


71. What do you called a compound motor with just one two series field turns?


72. A 12 volts is applied to the circuit where the resistance of R1 is 10 ohms and R2 is 10 ohms. What is the voltage across R2?


73. What will happen if you reverse both the field and the armature connections to DC motor?


74. An AC circuit has a capacitive reactance of 30 ohms in addition to an inductive reactance of 40 ohms connected in series. What is the reactance of the circuit?


75. When a mega ohmmeter is used to test the dielectric strength of wire insulation, the initial dip of the pointer toward zero is caused by ___.


76. If a magnetic controller contactor fails to pick up when the coil voltage is applied to the contactor coil, the cause maybe ___.


77. To equalize the power factor of two alternators operating in parallel, the __.


78. Which of the following effect if moisture absorbed in the windings or condensed on the surface of electrical machinery insulation?


79. What will happen to the current flow when the voltage remains constant, and the resistance increase in a series circuit?


80. Which of the following statements represents the difference between a relay and a contactor?


81. What is the purpose of DC generator brushes?


82. The most common type of AC service generator found aboard ship is the stationary ___________.


83. Which of the following has a similar function of a rectifier?


84. Which of the following statements describes what will happen when both the polarity of the field poles, and the direction of current to the brushed of a DC motor are reversed?


85. Which of the following is a general rule and the first troubleshooting action to be taken in checking faulty electric control devices?


86. What do you called a device that most commonly utilizes the principle of electromagnetic induction?


87. What is the function of damper windings in a synchronous motor?


88. What will you do first when securing an AC generator?


89. A voltage regulator installed in a direct current generator, serves the purpose of_______.


90. The speed of a multi-speed, squirrel-cage, induction motor operating in a fixed frequency system can be changed by ___.


91. Which of the following precautions should be taken when shore power is being connected to a ship in dry dock ?


92. Which of the following statements is correct concerning AC circuits?


93. Which of the following protect a circuit from overheating?


94. What is the main purpose of an electric space heater installed in a large AC generator?


95. What is the basic measuring unit of inductance?


96. Which of the following methods should be used to test for an open coil in an AC motor stator?


97. What does it means when an AC generator panel fitted with both synchronizing lamps and the synchroscope pointer reaches the noon position, one synchronizing lamps is bright and the other is dark?


98. Which of the following device protects against overheating in a electrical circuits?


99. A low horsepower with full voltage, polyphase , induction motors can be started by means of ___.


100. Two diesel generators operating in parallel, the load sharing characteristics are mostly dependent on their governor ___.


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