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1. C5 - What is the characteristic of the mica used in the commutators of DC machinery?


2. C5 - Regarding an induction motor, where is the output power developed related to?


3. C5 - What type of AC single-phase motor will also operate on direct current?


4. C5 - What do you call an AC motor which uses rheostat in the motor circuit to vary the speed?


5. C5 - Which of the following is the most common of excitation for synchronous motor?


6. C5 - Which of the listed transformers uses a single winding to produce voltage transformation?


7. C5 - What type of electric motor is commonly used to start small auxiliary diesel engines?


8. C5 - Which of the following electric motors would be the most reliable to use on the open main deck of a vessel?


9. C5 - When a megohmmeter is used to test the dielectric strength of wire insulation, what causes the intial dip of the pointer toward zero?


10. C5 - On a modern 13 amp square pin electric plugs, which of the following statements is true ?


11. C5 - The timer element of a reverse power relay will activate when ___


12. C5 - The difference between the synchronous speed of a three phase induction motor and its operating speed is called slip and may be correctly expressed as_______.


13. C5 - What determines the cycle per second developed by the alternator aboard your vessel?


14. C5 - Which of the following statements identifies the difference between the primary windings and the secondary windings of a 2:1 step down transformer?


15. C5 - What will happen if there is a change in field excitation of an alternator operating in parallel?


16. C5 - What is the advantage of DC motors over AC motors?


17. C5 - A galvanometer is an instrument used to measure ____.


18. C5 - Regulations require emergency diesel engine starting systems to have sufficient capacity to provide power for at least ____.


19. C5 - In a three-phase, open-delta connected transformer, the line current is equal to ____.


20. C5 - In a running electric motor, why are we using a sound listening bar?


21. C5 - Why is an armature cores in a DC generator made of laminated steel sheets?


22. C5 - What will be the next step after closing the circuit breaker to place two similar alternators in parallel?


23. C5 - What is the reason why one of the generator or motor bearings generally insulated from the end housing?


24. C5 - Why is a modern DC generators fitted with commutating poles?


25. C5 - Why is there an amortisseur windings installed in a synchronous motor?


26. C5 - What is the function of the interpoles installed in DC motors?


27. C5 - What is the purpose of squirrel-cage windings in a synchronous motor?


28. C5 - When energizing a DC propulsion motor using Local override manual control, What should the variable resistor do?


29. C5 - What is an operating characteristic appearing on the name plates of shipboard AC motors?


30. C5 - When mixing electrolyte, which if the following precautions should always be observed?


31. C5 - If the approximate voltage to be measured in an electric circuit is not known, you should _____.


32. C5 - The basic operating principle of a transformer is attributed to ___.


33. C5 - How is kilowatt load divided between two AC generators operating in parallel?


34. C5 - An increase in which of the listed conditions will increase the speed of synchronous electric motor?


35. C5 - Which of the following meters uses a shunt connected in series with the load, but parallel with the meter movement?


36. C5 - How is the capacity of a storage battery being measured?


37. C5 - A general purpose electrical multimeter can be used to directly measure ____.


38. C5 - A ‘dead front’ switchboard is one ____.


39. C5 - When the feeder system has no ground fault, what does the pointer of the insulation resistance indicates


40. C5 - Why is it desirable to operate paralleled AC generators at the same power factor?


41. C5 - A circuit breaker differs from a fuse, in that a circuit breaker_________.


42. C5 - "Due to the operating characteristics of the system, time lag fuses _______. (or dual-element fuses) are necessary for use in "


43. Basic electrical motor action depends on _______________.


44. Amortisseur windings are installed in a synchronous motor to_____. .


45. In an induction motor, rotor currents are circulated in the rotor by________. .


46. Regarding an AC generator connected to the main electrical bus; as the electric load and power factor vary, a corresponding change is reflected in the generator armature reaction. These changes in armature reaction are compensated by the ________. .


47. C5 - One important difference between wye-connected and delta-connected generators is that delta connections have ____.


48. C5 - The load sharing characteristics of two diesel alternators operating in parallel are directly related to the setting of their governors’_____.


49. C5 - Why is the engine room watch officers should keep a constant check on the loads carried by electric motors?


50. C5 - Which of the listed conditions could cause a recently overhauled DC motor to have excessively hot winding and sparking at the brushed?


51. C5 - Which of the following starting system should be carried out after overhaul of a motor?


52. C5 - What is the common source of field excitation for synchronous motors?


53. C5 - What is a component used to protect the DC generator circuits against malfunctions due to prime mover power loss?


54. C5 - Equalization of the power factors of two alternators operating in parallel is accomplishedin what manner?


55. C5 - Which of the following electrical instrument is the safest to use in taking the current even without switching off or opening the circuit?


56. C5 - Relative to the secondary winding of a step-up transformer, the primary winding will have ____.


57. C5 - What will happen if connections on a DC shunt motor are changed on either the field connections, or the armature connections?


58. C5 - What is the purpose of DC generator brushes?


59. C5 - A switchboard for an AC electrical system requires the use of which of the following devices?


60. C5 - A bus disconnect link is used to isolate ___.


61. C5 - The purpose of a magnetic relay is to ______.


62. C5 - As storage battery for an emergency lighting and power system must have the capacity to ____.


63. C5 - 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. What are these devices?


64. C5 - What protects a molded-case circuit breaker against sustained overload?


65. C5 - The shunt of a DC ammeter should be connected in _____.


66. C5 - When a transformer is used to step-down voltage, the low voltage winding is ___.


67. C5 - What inidicates a violent gassing developed by a lead-acid battery during charging?


68. C5 - When the non-essential load has been removed from the feeder system but the service generator remains overloaded, what device automatically activates?


69. C5 - What is the function of capacitors which are commonly used on power supply circuits for engine room automation consoles?


70. C5 - What do you call the device where a low input voltage is imparted to it which then delivers a high output voltage?


71. C5 - What electrical component intitiates the division of the reactive KVA load between paralleled AC generators?


72. C5 - The circuit power factor of an AC generator operating singularly is determined by the ____.


73. C5 - What do you call a torque produced by a motor when the shaft will not turn, even though rated voltage is applied to the stator?


74. C5 - What will happen if you reverse the DC current flow through an electrical coil?


75. C5 - Which of the following provides the initial torque to turn a DC generator?


76. C5 - The division of kilowatt load between two AC generators operating in parallel is controlled by the settings and characteristics of the ____.


77. C5 - On some diesel-electric ships, the DC propulsion motor will only attain half speed when the generator fields are fully excited. How should the speed above this be obtained?


78. C5 - What do you call a DC generator used to supply direct current in order to maintain an AC generator field?


79. C5 - Transformer cores are laminated to reduce ____.


80. C5 - To test the feeder system for grounding, the three earth lamps will be activated when this switch is manipulated.


81. C5 - A transformer works on the basic principle of ____.


82. C5 - What is the simplest method of controlling the terminal voltage of compound-wound DC generator?


83. C5 - Which of the following types of motor has two separate field windings usually connected in parallel with the armature circuit?


84. C5 - Which of the following types of motor whose speed at normal operation is constant or practically constant?


85. C5 - How would you describe a circuit with a blown fuse?


86. C5 - Which of the following operating characteristics for DC motors is considered to give high starting torque?


87. C5 - The resistance value of a resistor in a circuit can best be determined by the ______.


88. C5 - What is the recommended practice on the frequency of the incoming machine prior to closing the breaker when paralleling two AC generators?


89. C5 - When two AC generators are being paralleled, the breaker should be closed with the synchroscope pointer rotating in what direction?


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