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1. An open shunt field in a direct current machine may be located by connecting the field circuit to an external power source, equal to the rated field voltage or less, and tested with a voltmeter from _____________.


2. The timer element of a reverse power relay cannot be energized unless ___.


3. In the flow of one cycle of single phase AC current past any given point in a circuit, the maximum current peak occurs _


4. The safest time to close the ship’s main switchboard “shore power” circuit breaker would be ____.


5. When using an ohmmeter to test a semiconductor diode, you find a low resistance in both the forward and reverse bias directions. This indicates that the diode has a/an_____.


6. The purpose of a magnetic relay is to ______.


7. An accidental path of low resistance, allowing passage of abnormal amount of current is known as a/an_______ .


8. Inductance is the property of an electric circuit that _____.


9. Which of the damages listed can occur to the components of a winch master control switch, if the cover gasket becomes deteriorated?


10. On an engine throttle control system, the auxiliary control circuits are provided with devices to prevent excessive over travel of the actuating valve by the control motor.


11. An Ac generator is prevented from becoming motorized by the use of a/an _


12. Protection against sustained overloads occurring in molded-case circuit breakers is provided by a/an ____.


13. The ‘dielectric constant’ is a numerical value indicating the effectiveness of a dielectric material in comparison to that of a standard, which is _


14. To minimize magnetic field interaction between electrical conductors in physical proximity, it is best to keep them ______.


15. The shunt use in an ammeter should be connected in_______. .


16. The number of cycles per second occurring in AC voltage is know as the ______.


17. The method used to produce electron emission in most vacuum tubes is known as __


18. Germanium semiconductor diodes are commonly used as______


19. If the excitation of an alternator operating in parallel is decreased below normal, its ____


20. The purpose of a main switchboard circuit breaker’s reverse power trip is to ____


21. Capacitors are commonly used on power supply circuits for engine room automation consoles to______.


22. The purpose of having low voltage protection for an electric motor circuit is to ___.


23. The main purpose of an electric space heater installed in a large AC generator is to ____.


24. When a low input voltage is imparted to a device which then delivers a high output voltage, the device is known as a _


25. The output voltage of a 440 volt, 60 hertz, AC generator is controlled by the___


26. A magnetic relay is most commonly used to ____.


27. Nickel-cadmium storage batteries are superior to lead-acid batteries because they ____.


28. The governor control switch of an alternator is moved to the ‘raise’ position. This action will ___.


29. The combined effect of inductive reactance, capacitive reactance, and resistance in an AC series circuit is known as _____.


30. Large cable sizes are formed as individual conductors that may be comprised of several smaller strands to ____.


31. Which of the listed devices is used to measure pressure and convert it to an electrical signal?


32. An AC circuit has capacitance arranged in series. If the line voltage remains constant, the capacitive reactance value can be varied by changing the _____.


33. The force that causes free electrons to flow in a conductor producing electric current is called ______.


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


35. In an AC circuit, the inductive reactance of a coil varies with the ___


36. A semiconductor that decreases in resistance with an increase in temperature is known as a_


37. On some diesel-electric ships, the DC propulsion motor will only attain half speed when the generator fields are fully excited. Speeds above this are obtained by__


38. A DC generator which is used to supply direct current in order to maintain an AC generator field is commonly known as a/an ______.


39. The air gap in an induction motor should be checked periodically with a feeler gauge, to prevent possible ____.


40. Loss of residual magnetism in an alternator or generator can be corrected by _____?


41. Which of the following electric motors would be the safest and most reliable to use on the main deck of a vessel in foul weather conditions?


42. A molded-case circuit breaker provides protection against short circuits by using a/an


43. Any electric motor can be constructed to be __


44. The leads from an ohmmeter are attached to the leads of an AC motor field coil. A reading of infinity indicates_____


45. A ground can be determined as an electrical connection between the wiring of a motor and its


46. Which of the following materials is a good electrical insulator?


47. While on watch in the engine room at sea with only one ship's service turbine alternator on line, the entire plant suddenly blacks out without warning. After restoring power, the cause for this casualty was attributed to which of the following faults?


48. A motor using a rheostat in the motor circuit to vary the speed is called__


49. The purpose of the automatic bus transfer is to ____.


50. Capacitance in an AC circuit will ____.


51. Motor controllers are seldom troubled with grounds because ___.


52. A result of an overloaded circuit __________.


53. While on watch in the engine room, you are setting up to parallel alternators. The switchboard has a synchroscope and synchronizing lamps. If the synchroscope is broken, which of the steps listed is the most essential before an alternator can be parallel with the bus?


54. If a shipboard AC generator experiences voltage failure, the cause may be due to ____.


55. Why is it a poor practice to use a high wattage soldering iron when soldering or desoldering components on a printed circuit board?


56. The KW is evenly distributed between two alternators just placed in parallel by adjusting _


57. Motorization of an AC generator is undesirable because ____.


58. An AC generator panel is fitted with two synchronizing lamps and a synchroscope. When paralleling, if the synchroscope pointer is at the noon position and one synchronizing lamp is bright while the other remains dark, this indicates that ___.


59. You are in the process of paralleling two AC generators and the synchroscope pointer has stopped at a position other than 0º. This indicates that ___


60. When replacing a defective transformer in a parallel transformer configuration, which of the following actions must be carried out to ensure proper operation of the equipment it serves?


61. Prior to using an analog type ohmmeter, the leads are purposely shorted together. Which of the following actions should be taken if, when adjusting to ‘zero’ ohms, the indicating needle can not be returned to ‘zero’ on the scale?


62. An autotransformer is equipped with a 50% tap, a 65% tap and an 80% tap. Which of the following statements is true concerning a load connected to 50% tap?


63. The operating torque of the disk or timer element in an AC reverse power relay is obtained from _


64. An insulation resistance test is performed on a particular piece of electric instrument. In addition to the resistance reading, what information listed below should be entered in the electrical log?


65. Which of the following conditions will occur if the solenoid coil burns on a cargo winch with an electrical brake?


66. The amount of voltage induced in the stator windings of a modern AC generator depend mainly on ____.


67. The timer element of a reverse power relay will activate when ___


68. The cycle per second developed by the alternator aboard your vessel is determined by ___


69. Which of the following statements is true concerning step-down transformer operation?


70. Which of the following statements concerning analog and digital devices are correct?


71. In a three-phase electrical system. Three ground detecting lamps are provided. If all three lamps REMAIN at half brilliance when the ground detecting test switch is operated ___.


72. The number of cells in a 12 volt lead-acid battery is__


73. When troubleshooting electronic equipment, you should use a high impedance multimeter _______.


74. The conversion of constant frequency power into adjustable frequency power in a modern AC propulsion drive system is commonly achieved through the use of_


75. The timer element found in a reverse power relay obtains it operating torque via ___


76. One important difference between wye-connected and delta-connected generators is that delta connections have ____.


77. The effect of carrying field excitation excessively high on the synchronous motor will result in a


78. Materials that retain a large part of their magnetization, after the magnetizing force is removed, are said to have ______.


79. Electrical machinery insulation will break down more rapidly to ___


80. A current-carrying conductor makes accidental contact with a wiring conduit. This will be indicated by a ___.


81. A direct current passing through a wire coiled around a soft iron core is the description of a simple______.


82. AC generator are protected against malfunctions due to prime mover power loss by the use of ____.


83. The purpose of the reverse power relay, provided on a ship’s service panel, is to trip the circuit in the event of __


84. The charge of a lead-acid battery is checked with a ____.


85. A hydrometer measures specific gravity by comparing the ____.


86. Magnet chatter or 'pumping' occurring in a magnetic contactor can be caused by_______


87. A circuit breaker differs from a fuse in that a circuit breaker ____.


88. A signal derived from a controlled function and returned to the initiating point is called a/an_____


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


90. Relative to the secondary winding of a step-up transformer, the primary winding will have _


91. If the centrifugal switch or relay used for cutting out the starting winding of a split-phase induction motor fails to open once the motor is in operation, the ____.


92. Nickel-cadmium batteries are superior to lead-acid batteries at high discharge rates because they ____.


93. Which of the following statements represents the important factor that must be considered when replacing a faulty diode in a generators excitation field rectifier assembly?


94. Which of the listed battery charging circuits is used to maintain a wet-cell, lead-acid, storage battery in a fully charged state during long periods of disuse?


95. An AC generator operating in parallel loses its excitation without tripping the circuit breaker. This will ____.


96. One factor that determines the frequency of an alternator is the_______. .


97. The frequency output of an operating alternator is controlled by the___


98. A switchboard for an AC electrical system requires the use of which of the following devices?


99. Alternating current circuits develop resistance, inductance and capacitance. The inductance of a coil is expressed in _____.


100. A bus disconnect link is used to isolate ___.


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