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1. A circuit breaker & a fuse are similar because they both___________.


2. A device which prevents action occurring until all other required condition are met is a/an__________.


3. In induction motor, the rotor currents are circulated in the rotor by__________.


4. Heat sinks are frequently used with__________.


5. A circuit breaker differs from a fuse in that a circuit breaker__________.


6. Constant output from an AC generator is maintained by the__________.


7. What should be done to prevent moisture damage to electrical apparatus during extended periods of idleness?


8. The ground can be defined as an electrical connection between the wiring of motor and its___________.


9. Low horsepower polyphase induction motors can be started with full line voltage by means of___________.


10. An unknown resistance in circuit to be tested using the voltmeter method. The meters should be connected such that __________.


11. Thermal acting breaker must be used in an area of unusually high, low or fluctuating temperatures, an ambient compensating must be used consisting of a __________.


12. Electrolyte used in nickel-cadmium battery is__________.


13. Accidental path of low resistance which passes an abnormal current is known a/as__________.


14. What could be an application for a silicon controlled rectifier?


15. Which of the following is true concerning a polyphase synchronous propulsion motor?


16. What is the main difference between a relay & a contactor?


17. What type of type of rotor is used in split phase motors?


18. Which is a true statement about the circuits in a sound powered telephone system?


19. What does a wound rotor induction motor have which a squirrel cage motor does not?


20. The frequency of an operating alternator is controlled by the__________.


21. Capacitance in an AC circuit will __________.


22. In an AC circuit, the inductive reactance of a coil varies with the ___________.


23. A 4-pole, 60 Hz, 3-phase synchronous motor comes up to 1760 RPM when started as an induction motor. What is the percent slip after the rotor field is energized?


24. When connecting a three-phase induction motor where damage results from the wrong direction of rotation, you should __________.


25. The instantaneous reduction in voltage resulting from an increase in load before the automatic voltage regulation can correct it an AC generator is called voltage_________.


26. The energy consumed by an AC motor, as strictly reactive power is ___________.


27. To effectively clean a commutator in good physical condition, you should use __________.


28. Which of the listed faults cannot be eliminated, except by turning or grinding a commutator with a rigidly supported tool?


29. When fluorescent lamp has reached the end of its useful life, it should be replaced immediately, or the resultant flashing may _________ .


30. What is the purpose of the capacitors on the output of the power supplies used in today


31. When disassembling motor for maintenance or overhaul, ___________.


32. Which of the following procedures should be used to maintain a large electric motor during periods of inactivity?


33. If a small electric motor has been submerged in saltwater for a short period of time, you should ___________.


34. Which of the following methods should be used to dress the face of silver-plated contacts?


35. Grease coating on electrical contact surfaces increase contact resistance and should be removed with a/an __________.


36. Which statement is true concerning the maintenance of solid-silver contacts in relays and auxiliary control circuits?


37. You are troubleshooting a magnetic controller and find the contacts are welded. The most probable cause is ___________.


38. Which of the following precautions should you take when securing propulsion generators and motors for an extended period of time?


39. Which of the following statements, concerning the general maintenance of a brushes generator, is correct?


40. On large generators, space heaters are used to __________.


41. What material is recommended for finishing slip rings after grinding or turning?


42. Silicon diodes that are designed for a specific reverse breakdown voltage and thus become useful as electronic power supply voltage regulators is/are called __________.


43. Where a thermal-acting breaker must be used in an area of unusually high, low, or fluctuating temperatures, an ambient compensating element must be used consisting of a __________.


44. Which of the following statements is true concerning the cleaning of electrical contacts?


45. Which of the listed procedures should be carries out to prevent moisture damage to electrical apparatus during extended periods of idleness?


46. The unit of apparent power in a purely inductive circuit is called the __________.


47. If overloading a DC machine becomes necessary in an emergency, you should __________.


48. The formula for computing impedance in a series circuit containing resistance, capacitance, and inductance is __________. (Note: the symbol * stands for multiplied by)


49. Voltage will always lead current in a/an __________.


50. When voltage and current developed in an AC circuit reach their peak values at the same time, the power factor is ___________.


51. In an alternating current electrical system, a low system power factor is a direct sign of ___________.


52. The voltage of an operating AC turbo generator is raised or lowered by adjusting the ___________.


53. The frequency of an alternator at a given RPM is determined by the __________.


54. Autotransformer starters or compensators are sometimes used with poly-phase induction motors to __________.


55. The ratio of the effective value of the counter EMF in volts to the effective value of the current in amperes is called ___________.


56. A constant output voltage from AC generator is regulated by the __________.


57. The frequency of an alternator is controlled from the main switchboard by adjusting the __________.


58. Which procedure should be used to determine the load on a three-phase delta-connected AC generator?


59. The reactive power drawn by a motor from an AC generator is the power which is __________.


60. The removal of paint from electrical equipment, such as generators, should be cautiously undertaken because __________.


61. Periodic testing by a shoreside support technician using a special camera which can detect potentially dangerous loose or corded bus bar and controller connections is termed _________.


62. When troubleshooting an electronic circuit, a cold solder joint can be located with the aid of an ohmmeter. Once the problem has been located, you should _________.


63. To protect the rotor of a motor disassembled for maintenance of overhaul, it should be __________.


64. Which of the listed precautions should be observed before spraying liquid solvent on the insulation of an electric motor?


65. Encrusted dirt accumulated inside a motor should be removed with a __________.


66. Which of the following represents the accepted method of cleaning dust and foreign particles from electrical equipment while limiting damage to electric components?


67. When an alternator is to remain idle for even a few days __________.


68. Damp armature windings in a D.C. motor may lead to __________.


69. Which type of flux should be used when soldering electrical wire connections and electronic components?


70. When the voltage and the current developed in an AC circuit reach their peak values at the same time, the power factor is considered to be __________.


71. Which is a function of voltage regulators used with AC generators?


72. The voltage of an alternator is normally controlled by varying the ___________.


73. The voltage generated by an AC generator is controlled by varying the ___________.


74. Before reassembling any machinery, you should __________.


75. Two contributors of electronic console failures are heat and vibration to combat some of their effects, preventive maintenance procedures should include __________.


76. Automatic voltage regulators on DC generators detect voltage changes and adjust the __________.


77. When removing ball or roller bearings from the shaft of a motor, always use a ___________.


78. Which of the following materials is recommended for finishing the slip rings after grinding or turning?


79. Unnecessary and frequent applications of varnish to the generator windings to repair defective insulation will result in ___________.


80. The purpose of a main switchboard circuit breaker reverse-power trip is to ___________.


81. Compressed air should not be used to clean motor controller equipment because __________.


82. Machinery with ball bearings designed to be filled with grease should have the relief plug temporarily removed after grease has been added. This plug should remain out until the machinery has been operated and sufficiently warmed up to ensure that __________.


83. If an alternator is to be inactive for a considerable period of time, which of the following actions should be taken?


84. The apparent power in a purely inductive circuit is also called the __________.


85. What is the basic unit of inductance?


86. Freezing point of electrolyte in a fully charged lead-acid battery will be__________.


87. A fuse that blows should be replaced only with a fuse of __________.


88. What is an advantage of a PN diode over a vacuum diode?


89. While you are starting a main propulsion synchronous motor as an induction motor, the ampere meter pegs out a maximum & then returns to proper value after synchronization, this means the_________.


90. The greatest detrimental effect on idle electrical equipment such as cargo pump motor is __________.


91. The wheatstone bridge is a precision instrument used to measure__________.


92. Which statement is correct statement concerning an analog device & digital device?


93. Molded-case circuit breaker provides protection against short circuit by using a/an__________.


94. Which motor that fitted with an instantaneous overload relay?


95. The alarm system for an engine order telegraph uses small selsyn motors attached to the indictors. The alarm sounds when the rotor are__________.


96. A degree of control over the speed of a slip ring induction motor can be obtained by__________.


97. Non-adjustable molded case circuit breaker are classified by frame size, ampere rating, & interrupting capacity. The frame size is express in__________.


98. Which of the following precautions when securing propulsion generators & motors for extended period of time?


99. The current at which magnetic type overload relay tends to trip may be decreased by raising the plunger further into the magnetic circuit of the relay. This action __________.


100. Which of the following logic gates is/are considered to a basic bldg. block (basic logic gate) used in logic diagrams?


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