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1. If a digital multimeter is set up as shown in figure "A" of the illustration, what would be displayed on the screen if the fuse being tested is blown? EL-0210


2. If a circuit breaker that utilizes built-in, current limiting fuses (CLF's), cannot be closed or reset, what may be the problem? I. A blown current limiting fuse due to a short-circuit condition II. A missing current limiting fuse


3. The ground indicating light on the main electrical switchboard is indicating a ground. What is the best procedure for locating the grounded circuit?


4. Before any work on electrical or electronic equipment is performed, which of the following precautions should be carried out?


5. Which of the following expresses the relationship of the AC input frequency and DC ripple output frequency in a full wave rectifier?


6. In process control terminology, continuously variable values which change without distinct increments, such as temperature, pressure, or level are correctly referred to as what type of values?


7. Which of the listed conditions describes the effect on intrinsic semiconductor operation as a result of a temperature increase?


8. What is the functional purpose of a heat sink, as frequently used with transistors?


9. What is the third color band on a resistor used to indicate?


10. A saturable-core reactor operates on the principle of controlling a load winding's inductance by changing the permeability of the core. How is this accomplished?


11. What will happen to a carbon resistor operating in electrical equipment that is NOT properly cooled?


12. Which of the procedures or conditions listed could result in damaging a transistor beyond repair?


13. An ohmmeter used to test for front-to-back resistance of a PN junction diode should produce roughly what ratio?


14. What should be done with a capacitor that is obviously discolored due to excessive heat?


15. In order to check the performance of a transistor removed from its circuit, what meter or tester should be used?


16. Which of the following conditions would most likely lead to the failure of a resistor due to overheating?


17. What would be the indication of a burned-out LED?


18. What is the most common and reliable type of circuit breaker used for high voltage practice aboard ship?


19. Some shipboard high voltage systems have the neutral point of the generators bonded to the ship's hull with a neutral grounding resistor? What is the purpose of this resistor?


20. Suppose it is desired to determine the integrity of the insulation of a 4160 VAC motor. What type of insulation resistance tester (megger) would be suitable?


21. Before work may safely commence on a high voltage system, what must first be done after disconnection and isolation?


22. In order for a live-line tester to be used to test and prove dead a high voltage circuit, what must be done to verify the ability of the tester to detect a voltage?


23. In addition to high voltage circuit grounding with ground-connecting switching devices, for additional operator safety and confidence, portable grounding straps may be used. What is the proper procedure for connecting these portable grounding straps?


24. When completing repairs on a high voltage circuit where portable grounding straps were used for increased operator safety and confidence, what is the proper procedure for disconnecting these grounding straps?


25. For a motor rated at 3.3 kV, what would be a minimum accepted insulation resistance to hull ground as tested by an appropriate megger (insulation tester)?


26. When an high voltage system insulation test value is suspect or recorded during an annual survey, a polarization index test is performed. What is the polarization index?


27. On vessels with AC distribution systems, which of the following statements represents the most difficult problem involved in obtaining a DC potential suitable for use by computer components?


28. What statement is true concerning read only memory (ROM)?


29. What statement is true concerning random access memory (RAM)?


30. Which of the following devices represents primary storage, where the processor is able to directly read instructions and data and directly return results of its computation in fetch/execute cycles?


31. Which of the following data communication cable types offers the greatest immunity to electromagnetic "noise"?


32. What type of local area network physical topology features point-to-point interconnection between all communicating devices and is the least vulnerable to a break in communication?


33. Modern ships use multiple computers arranged in a client/server network to perform various shipboard functions. What type of computer network would most likely be used aboard ship?


34. What Ethernet cabling technology supports the greatest data transfer speeds?


35. If an 8-bit digital to analog converter (DAC) produces an analog output voltage with a range of 10 volts (0-9 volts), what is the smallest incremental step in voltage that can be generated at the output?


36. If a computer display is flickering, how may this be remedied?


37. In mounting a transducer for a depth sounding system, what would represent an ideal location?


38. Two AC generators of the same capacity are operating in parallel. One with a zero speed droop setting and the other with a 5% speed droop. If its capacity is not exceeded, what will be the characteristic of the unit whose governor has the zero speed droop setting?


39. As Chief Engineer, to prevent the motorization of an alternator what safety device would you have checked quarterly?


40. What may be the cause of an AC generator to fail to produce a voltage?


41. ( While underway onboard a DC diesel electric drive ship, you notice excessive sparking of the brushes on the main propulsion motor. What should be your FIRST action?


42. Upon failure of the normal power supply, how is the emergency generator placed on the line to feed power to the emergency bus?


43. For the purposes of safety and determining the shock hazard, nominal voltage is defined as the normal electrical system design voltage. This can be determined from what is displayed on nameplates, data plates, schematics, or single-line diagrams. What does the nominal voltage represent?


44. What is the minimum threshold voltage at which the skin offers no appreciable resistance to electrical current flow and is known as the "skin-puncture voltage"?


45. Which activity or event accounts for the most electrical accidents resulting in injury?


46. Why should an electrical worker determine the nominal voltage of a circuit first before making contact with the circuit?


47. When taking voltage measurements, for reasons of electrical safety, what should be the proper sequence of actions?


48. When performing an absence-of-voltage test before commencing repair work, at the minimum where must the absence-of-voltage test be performed?


49. When performing an absence-of-voltage test, a live-dead-live test may be required in conjunction with the absence-of-voltage test. What is the purpose of the live-dead-live test?


50. What statement is true concerning temporary protective grounds used to establish an equipotential zone for the purposes of eliminating the electric shock hazard?


51. What is the minimum threshold voltage which requires electrical workers to be insulated from energized conductors or circuit parts by wearing the appropriate PPE while working in open enclosures?


52. How are power transformers rated?


53. Why are transformer cores laminated?


54. Which of the listed sections of an emergency switchboard is used to supply power for alarm signals under emergency conditions?


55. The timer element of a reverse power relay cannot be energized unless what condition is met?


56. When electrical cables penetrate watertight bulkheads, what must be provided for?


57. What is the reason that some electric cables are formed of stranded wire?


58. Which of the following characteristics is most critical in determining the wire gauge size of the cable to be used in a particular circuit?


59. How are the line losses in a distribution circuit kept to a minimum?


60. Why is it necessary to perform periodic testing of correctly rated and properly installed circuit breakers?


61. What should be done when performing maintenance of circuit breaker contacts?


62. Which of the listed classes of electrical insulation is suited for the highest operating temperature?


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


64. To check the three line fuses protecting a three-phase motor using a multimeter set up as a voltmeter, what should be done FIRST?


65. As a general rule, what is the first troubleshooting action to be taken in checking inoperative electric circuits?


66. To test fuses in an energized circuit, what testing apparatus or meter should be used?


67. When replacing a fuse with one of a ampere higher rating than the original, which of the following is true?


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