USCGQ
Log in Start free
USCGQ
Toggle sidebar
Home
Engine
Electricity
Start practicing

Engine · 1,595 questions

Electricity - USCG Exam Questions

Marine electrical systems: motors and generators, switchboards and distribution, batteries, electronics, and control engineering.

Every question below is a real U.S. Coast Guard exam question with four choices. Answer one and the correct choice is revealed instantly, with the USCG reference and illustration where the question uses one.

Random question Build a timed exam

All Electricity questions

Questions 1,301–1,400 of 1,595 · page 14 of 16

  1. #1302 As shown in figure "C" of the illustration, what are the purposes of the coupling capacitor Cc and the bypass capacitor Cbp respectively. EL-0045 illustration
  2. #1303 As shown in figure "A" of the illustration, what type of converter unit is represented? EL-0240 illustration
  3. #1304 As shown in figure "B" of the illustrated function block for a PLC PID controller, to what input is the actual analog signal of the measured value del... illustration
  4. #1305 If the clock frequency input to the circuit shown in the illustration were 2 kHz, what would be indicated at the output of 'FF-3' at the Q3 output? EL... illustration
  5. #1306 What is the name of the digital logic gate represented by figure "1" of the illustration? Illustration EL-0035 illustration
  6. #1307 On a digital numerical display readout, what would be the minimum number of LED segments required to form and display any digit 0 through 9?
  7. #1308 As shown in figure "A" of the illustration, what is the configuration of the operational amplifier? EL-0252 illustration
  8. #1309 In process control terminology, continuously variable values which change without distinct increments, such as temperature, pressure, or level are cor...
  9. #1310 As shown in figure "B" of the illustrated block diagram of the signal processing flow path, what does the block "TRANSDUCER" represent? EL-0095 illustration
  10. #1311 As shown in the illustrated block diagram for a distributed automation system, what statement is true concerning the area networks? Illustration EL-00... illustration
  11. #1312 As shown in figures "A", "B", and "C" of the illustration, what is the purpose of the differential amplifier segment of the 741 operational amplifier?... illustration
  12. #1313 As shown in the illustration, which electrical symbol represents a PNP type bipolar junction transistor? EL-0065 illustration
  13. #1314 As shown in figure "A" of the illustration, what is true concerning the illustrated frequency response curve? EL-0076 illustration
  14. #1315 Which of the listed conditions describes the effect on intrinsic semiconductor operation as a result of a temperature increase?
  15. #1316 What does the electronic symbol of figure "9" represent? EL-0065 illustration
  16. #1317 As shown in figure "A" of the illustration, under what conditions will the thyristor conduct? EL-0154 illustration
  17. #1318 What is the functional purpose of a heat sink, as frequently used with transistors?
  18. #1319 What is the third color band on a resistor used to indicate?
  19. #1320 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 ac...
  20. #1321 What will happen to a carbon resistor operating in electrical equipment that is NOT properly cooled?
  21. #1322 A carbon resistor has a resistance of 50 ohms, and a tolerance of 5 percent. What would be the respective colors indicated for bands 1, 2, 3 and 4 for... illustration
  22. #1323 Which of the procedures or conditions listed could result in damaging a transistor beyond repair?
  23. #1324 An ohmmeter used to test for front-to-back resistance of a PN junction diode should produce roughly what ratio?
  24. #1325 If a digital multimeter is set up as shown in figure "A" of the illustration to test a capacitor, what would the display read if the capacitor is func... illustration
  25. #1326 What should be done with a capacitor that is obviously discolored due to excessive heat?
  26. #1327 If a digital multimeter is set up as shown in figures "A" and "B" to test a silicon diode, what is the status of the diode if the screen displays 0.70... illustration
  27. #1328 In order to check the performance of a transistor removed from its circuit, what meter or tester should be used?
  28. #1329 Which of the following conditions would most likely lead to the failure of a resistor due to overheating?
  29. #1330 What would be the indication of a burned-out LED?
  30. #1331 What is the most common and reliable type of circuit breaker used for high voltage practice aboard ship?
  31. #1332 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...
  32. #1333 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 su...
  33. #1334 Before work may safely commence on a high voltage system, what must first be done after disconnection and isolation?
  34. #1335 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 det...
  35. #1336 In addition to high voltage circuit grounding with ground-connecting switching devices, for additional operator safety and confidence, portable ground...
  36. #1337 When completing repairs on a high voltage circuit where portable grounding straps were used for increased operator safety and confidence, what is the...
  37. #1338 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 test...
  38. #1339 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...
  39. #1340 On vessels with AC distribution systems, which of the following statements represents the most difficult problem involved in obtaining a DC potential...
  40. #1341 What statement is true concerning read only memory (ROM)?
  41. #1342 What statement is true concerning random access memory (RAM)?
  42. #1343 Which of the following devices represents primary storage, where the processor is able to directly read instructions and data and directly return resu...
  43. #1344 Which of the following data communication cable types offers the greatest immunity to electromagnetic "noise"?
  44. #1345 What type of local area network physical topology features point-to-point interconnection between all communicating devices and is the least vulnerabl...
  45. #1346 Modern ships use multiple computers arranged in a client/server network to perform various shipboard functions. What type of computer network would mo...
  46. #1347 What Ethernet cabling technology supports the greatest data transfer speeds?
  47. #1348 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...
  48. #1349 If a computer display is flickering, how may this be remedied?
  49. #1350 According to the liquid crystal data display for the depth sounder shown in the illustration, what is the instantaneous depth currently being displaye... illustration
  50. #1351 Using the trouble analysis chart and faults table provided in the illustration, if the gyrocompass was malfunctioning, but no fault codes are present... illustration
  51. #1352 In mounting a transducer for a depth sounding system, what would represent an ideal location?
  52. #1353 In viewing the liquid crystal display for the illustrated depth sounder data display unit, what should be done if the graphic display of the ocean bot... illustration
  53. #1354 As shown in the illustrated block diagram for a digitized echo sounding system, what statement is true concerning the transmission and reception of ac... illustration
  54. #1355 As shown in the illustrated block diagram for a digitized echo sounding system, what statement is true concerning the function of the transducer? EL-0... illustration
  55. #1356 As shown in the illustrated graph showing the effect of overshoot on steering system control stability, what statement is true? EL-0188 illustration
  56. #1357 As shown in the illustrated adaptive digital steering control system functional block diagram and listed system interface signals table, what would th... illustration
  57. #1358 As shown in the illustrated adaptive digital steering control system functional block diagram and listed system interface signals table, what would th... illustration
  58. #1359 As shown in the illustrated digital gyrocompass functional block diagram and the associated communication protocols table, what would the rate of turn... illustration
  59. #1360 Assuming the alternator shown in figure "A" of the illustration is equipped with a diode plate as configured in figure "D", what is the purpose of the... illustration
  60. #1361 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 capa...
  61. #1362 What are the operational characteristics of the two alternators with the speed-droop curves shown in figure "A" of the illustration? EL-0025 illustration
  62. #1363 In preparation for paralleling generators, if the electric plant condition is as shown by graph "A", what would be the rotational status of the synchr... illustration
  63. #1364 From the illustration shown in figure "C", what can be determined from the speed droop characteristics of generator A and generator B? EL-0025 illustration
  64. #1365 As shown in figure "B" of the illustration, what is the purpose of the synchronous compensator? EL-0133 illustration
  65. #1366 As Chief Engineer, to prevent the motorization of an alternator what safety device would you have checked quarterly?
  66. #1367 As shown in the illustrated alternator protection scheme diagram, what device provides the input to the over current inverse time relay "OCIT", the ov... illustration
  67. #1368 As shown in the illustrated diagnostic setup for locating a shorted field coil of a ten- pole salient pole alternator, if 240 VAC 60-Hz is applied acr... illustration
  68. #1369 What may be the cause of an AC generator to fail to produce a voltage?
  69. #1370 As shown in the illustrated alternator protection scheme diagram, under what circumstances would an earth leakage relay (EL) be used? EL-0067 illustration
  70. #1371 As shown in the illustration, if the port propulsion motor field excitation circuit experienced a failure, what individual component failure would all... illustration
  71. #1372 While standing an "at sea watch" onboard a modern rectified DC diesel-electric drive ship you notice the transformer core temperature slowly rising. W...
  72. #1373 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...
  73. #1374 Upon failure of the normal power supply, how is the emergency generator placed on the line to feed power to the emergency bus?
  74. #1375 In the illustrated one line diagram, if the ship's service generator on line fails, what statement is true concerning the operation of the emergency d... illustration
  75. #1376 As shown in the illustrated one-line diagram of a two-tiered emergency power system for a passenger ship, what statement is true? EL-0166 illustration
  76. #1377 From the information given in the illustration, which of the following statements is correct? Illustration EL-0106 illustration
  77. #1378 Before any work on electrical or electronic equipment is performed, which of the following precautions should be carried out?
  78. #1379 For the purposes of safety and determining the shock hazard, nominal voltage is defined as the normal electrical system design voltage. This can be de...
  79. #1380 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...
  80. #1381 Which activity or event accounts for the most electrical accidents resulting in injury?
  81. #1382 Why should an electrical worker determine the nominal voltage of a circuit first before making contact with the circuit?
  82. #1383 When taking voltage measurements, for reasons of electrical safety, what should be the proper sequence of actions?
  83. #1384 When performing an absence-of-voltage test before commencing repair work, at the minimum where must the absence-of-voltage test be performed?
  84. #1385 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...
  85. #1386 What statement is true concerning temporary protective grounds used to establish an equipotential zone for the purposes of eliminating the electric sh...
  86. #1387 What is the minimum threshold voltage which requires electrical workers to be insulated from energized conductors or circuit parts by wearing the appr...
  87. #1388 What would be the total current of the illustrated circuit in figure "A" if the value of capacitor C1 was 100 microfarads, capacitor C2 was 200 microf... illustration
  88. #1389 A turbogenerator has a rated output of 1200 kW at 60 Hertz, with a no-load frequency of 61.5 Hertz. What is its speed droop?
  89. #1390 Of the images in figures "A" through "D", which represents the schematic symbol shown in Figure "2"? illustration
  90. #1391 Which electronic schematic symbol represents the capacitor in figure "1" of the illustration? illustration
  91. #1392 What is the most convenient instrument for measuring current, voltage and resistance?
  92. #1393 While troubleshooting a circuit in an engine room central control console, a resistor is suspected of being faulty. Which of the following precautions...
  93. #1394 In the illustration, what type of motor and motor starter are featured? illustration
  94. #1395 A digital multimeter is set up as shown in figure "A" to test an AC contactor coil, what would the display read if the coil is open-circuited? illustration
  95. #1396 In the illustration, what is the purpose of the Time Delay (TR) coil in the circuit? illustration
  96. #1397 Which of the following electric propulsion motor types requires no brushes or electrical connections to the rotor?
  97. #1398 With an AC synchronous electric propulsion motor driving a fixed-pitch propeller, whenever there is a direction reversal ordered from the bridge, ther...
  98. #1399 An AC diesel-electric drive ship with synchronous propulsion motors has the capability for power factor correction. If the power factor associated wit...
  99. #1400 An AC diesel-electric drive ship with synchronous propulsion motors has the capability for power factor correction. If the power factor associated wit...
  100. #1401 A fuse is the most common type of protection against a short-circuit fault in LV distribution circuits, motor circuits and for portable appliances. Wh...

Electricity questions: what to expect

Q How many Electricity questions are in the Engine pool?

There are 1,595 Electricity questions on this site, every one released by the U.S. Coast Guard or taken from the National Maritime Center's sample examinations, with its correct answer. The exam draws its Electricity module from the same pool.

Q What score do I need to pass the Electricity module?

Most USCG exam modules, including Electricity, require 70 percent to pass. Rules of the Road modules require 90 percent.

Q Are these the real USCG Electricity exam questions?

Yes. They are the published U.S. Coast Guard questions, matched to the National Maritime Center's 2026 sample examinations. Answer any question to see the correct choice, the USCG reference and the illustration where the question uses one.

Other Engine modules

About the Engine question pool

The Engine pool holds the current U.S. Coast Guard questions for engineering credentials, from QMED ratings through DDE and Assistant Engineer up to Chief. Answer any question to see the correct choice instantly.