Q625 - Electrical, Electronic, & Control Engineering, USCG prep certification 2026

Progress: 24% (23/94)

Learning progress ?

1. While monitoring an impressed current cathodic hull protection system, which of the following measurements should remain constant in a properly operating electronically regulated system?Not learned 2. In monitoring an impressed current cathodic hull protection system, it is important to ensure that the propeller screw receives the same cathodic protection as the hull. What should be checked?Not learned 3. Before any work on electrical or electronic equipment is performed, which of the following precautions should be carried out?Not learned 4. When placed in a magnetic field, which of the materials listed has the highest permeability?Not learned 5. At a minimum threshold, how many milliamps of current through the body produces a painful sensation that most people would perceive as an electric shock?Not learned 6. Contact with any energized electrical system conductor is potentially hazardous and precautions should be taken to prevent exposure. With all other factors considered equal (such as voltage, conducting path through the body and the duration of contact), contact with an energized electrical system conductor of which system type would produce the most damaging effect?Not learned 7. Which of the following devices would be forbidden to use as a primary means of electrical isolation?Not learned 8. 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?Not learned 9. Which of the substances listed can be used to shield sensitive equipment from static magnetic fields?Not learned 10. Which of the electrical schematic symbols shown in the illustration represents a normally closed limit switchNot learned 11. When electrical cables penetrate watertight bulkheads, what must be provided for?Not learned 12. How are the line losses in a distribution circuit kept to a minimum?Not learned 13. In a simple DC circuit, the resistance is held constant while the applied voltage is halved. What will be the effect on the current flow as compared to the original current?Not learned 14. In a series circuit, what is the applied voltage (or sum of the applied voltages) equal to?Not learned 15. What statement is true concerning the total resistance of a parallel circuit?Not learned 16. Which of the following statements is true concerning circuits with parallel connected resistances?Not learned 17. How should the shunt used in an ammeter be connected?Not learned 18. Which of the listed temperature measuring devices installed on a large turbo-electric alternating current propulsion generator would be the most reliable for monitoring generator temperatures to avoid premature winding insulation failure?Not learned 19. The shaft revolution indicator system for a fixed-pitch propeller has which of the following display capabilities?Not learned 20. What material are the plates of a wet cell NiCad storage battery made of?Not learned 21. What statement is true concerning the charging of a 100 amp-hour lead-acid battery?Not learned 22. What could prevent a lead-acid battery from accepting a full charge?Not learned 23. To keep emergency lead-acid batteries in a full state of charge for emergency use, what is normally done?Not learned 24. What is the nominal open-circuit cell voltage of one lead-acid storage battery cell?Not learned 25. What should you be aware of when checking the specific gravity of the battery electrolyte with a hydrometer?Not learned 26. When troubleshooting a lead-acid storage battery, what is the best method for detecting a weak or dead cell?Not learned 27. As the electrolyte level in the cells of a lead-acid battery evaporates over time, what will tend to happen to the specific gravity of the electrolyte in the cells as the level drops due to evaporation?Not learned 28. How can the loss of residual magnetism in an alternator with a brushless excitation system be corrected?Not learned 29. From the instant of start-up, through the acceleration period, and until the motor reaches rated speed, when is the counter EMF produced in the windings of a DC motor "zero"?Not learned 30. How can the direction of rotation of a DC motor be reversed?Not learned 31. What type of motor is generally used in DC propulsion drive systems?Not learned 32. What is the function of the movable cams in a master-switch winch motor drum controller?Not learned 33. What effect will increasing the power source frequency have in a capacitive circuit?Not learned 34. Which of the following pictures shown in the illustration is a control transformer, usually used to step down line voltage for supplying reduced voltage control circuitsNot learned 35. 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 the 50% tap?Not learned 36. If the primary winding of a particular voltage transformer rated for a given AC input voltage is mistakenly connected to a comparable steady DC input voltage with similar source impedance, selfinductance and mutual inductance are not possible. As a result, what part of the transformer will result in current overload?Not learned 37. What is the purpose of a potential transformer in an electric circuit?Not learned 38. Which of the following statements about a three-phase wye connected alternator is correct?Not learned 39. How are AC and DC generators similar?Not learned 40. If it becomes absolutely necessary to run an alternator at lower than 5% below its rated frequency, in terms of output voltage, what must be done?Not learned 41. Under unusual circumstances, it may be required to operate a ship's service generator above its rated kVA. What supplemental casualty control action will be required?Not learned 42. Upon loss of field excitation of a generator operating in parallel with others, what must be done?Not learned 43. How is the difference between the synchronous speed of a three-phase induction motor and its operating speed correctly expressed?Not learned 44. What is the characteristic of a wound-rotor induction motor, with a high resistance inserted in series with the rotor winding at startup?Not learned 45. Which of the following physical characteristics does a three-phase wound-rotor induction motor possess that a squirrel-cage induction motor does not?Not learned 46. Concerning the operating characteristics of a synchronous motor, what statement is true?Not learned 47. Assuming that a three-phase synchronous motor is separately excited, what statement is true concerning power supplies?Not learned 48. Occasionally a synchronous motor is configured without an external shaft to drive a load. In this case, the sole purpose of the synchronous motor is improving overall power factor of an electrical distribution system. What is the name of the synchronous motor so constructed?Not learned 49. Which statement is true concerning a split-phase induction motor?Not learned 50. What is the main purpose of the auxiliary winding on a split-phase, single phase motor?Not learned 51. A shaded-pole motor is a specific type of motor included in what class of motor?Not learned 52. A split-phase induction squirrel-cage motor will not start and come up to speed, even though the rated voltage and frequency are applied. Assuming that the motor hums without rotating, which of the following troubles would MOST likely be suspected?Not learned 53. Which type of AC single phase motor will also operate on direct current?Not learned 54. Of the following, what shipboard system is MOST likely to use the synchronous transmission system featuring a transmitter and receiver?Not learned 55. What is the name of the mechanism used to transmit rudder angle information from the steering gear itself to the wheelhouse in the illustrated rudder angle indicator systemNot learned 56. In figure "1" of the illustration, what type of circuit breaker trip element is featuredNot learned 57. What type of AC motor would use a rheostat in the rotor circuit to vary the speed of the motor?Not learned 58. Which of the following statements represents the main difference between an electromagnetic relay and an electromagnetic contactor as used in motor control and power circuits?Not learned 59. What is the name of the type of motor control circuit that will not permit automatic restarting after power is restored, following a power failure?Not learned 60. When power is restored after a complete power failure, how will the steering gear pump motor which was on- line respond?Not learned 61. Grounds occurring in electrical machinery as a result of insulation failure may result from deterioration over time and excessive heat. What could be another contributing cause?Not learned 62. As shown in figure "A" of the ungrounded distribution system, under what conditions would an outage likely occur due to a ground fault (or faults) causing a circuit breaker to tripNot learned 63. When a megohmmeter is being used to test insulation resistance, current leakage along the surface of the insulation is indicated by the megohmmeter's pointer responding in a very unique way. What would be the response of the pointer?Not learned 64. When testing insulation resistance of electric equipment and machinery, ideally when should the insulation resistance be tested for the lowest normal insulation values?Not learned 65. What would be the indication of a grounded switch or cable as measured by a megohmmeter?Not learned 66. Which of the following is the only known perfect dielectric for the purpose of serving as electrical insulation?Not learned 67. The electrical energy necessary to power a sound-powered telephone's small vibrating bell is obtained from what power source?Not learned 68. To facilitate communication between the wheelhouse and the steering gear room in a steering emergency where no external source of power is required, what means of two-way communication would be provided?Not learned 69. Which station's emergency loudspeaker must allow for two-way communication?Not learned 70. Assuming the vessel has an engine control room, where is an engineers' assistance-needed alarm required to produce an audible signal?Not learned 71. In the diagram of the switchboard shown in the illustration, if one of the turbines should fail due to a throttle trip, what will happenNot learned 72. The timer element of a reverse power relay cannot be energized unless what condition is met?Not learned 73. Upon failure of the normal power supply, by what means is the emergency generator placed on the line and connected to the emergency bus?Not learned 74. As shown in the illustrated harmonic analysis diagram, which figure represents the third harmonicNot learned 75. For the purposes of high voltage marine practice, what is the threshold voltage where all voltages below this value are considered low voltage?Not learned 76. 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?Not learned 77. 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?Not learned 78. 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?Not learned 79. Which of the following methods should be used to dress the face of silver-plated contacts?Not learned 80. What can be the cause of excessive heat or burning contacts in an operating motor controller?Not learned 81. Assuming that 450 VAC is the source voltage at the circuit breaker, if 450 volts AC were measured across the load as shown in figure "B" of the illustration, what would this indicateNot learned 82. A lightly loaded three-phase squirrel-cage induction motor, while running, begins to vibrate excessively but continues to run. After shutting down the motor, the motor will not restart, but makes growling noises, overheats, and smokes. What caused this?Not learned 83. What is the shape of the schematic symbol for an operational amplifier used in an analog circuit?Not learned 84. Ships requiring extremely rapid maneuvering response using propeller shaft speed and direction as the sole means of controlling propeller thrust are most likely to use what type of drive system?Not learned 85. Which of the following is a disadvantage of electric drive propulsion systems?Not learned 86. Which statement is TRUE concerning electric propulsion drives?Not learned 87. An electric propulsion drive system in which the propulsion generator supplies power to both the propulsion motor and ship service loads is referred to as what type of system?Not learned 88. What equipment for modern SCR rectified DC propulsion drive systems is usually included in the package?Not learned 89. Which of the electronic schematic symbols represents the capacitor illustrated in figure 4 of the illustrationNot learned 90. What is the name of the semiconductor that decreases in resistance with an increase in temperature?Not learned 91. What does the symbol in figure "1" shown in the illustration representNot learned 92. In referring to figure "A" of the illustration, what type of active filter circuit is shownNot learned 93. Which of the following statements concerning analog and digital devices is correct?Not learned 94. Which of the procedures or conditions listed could result in damaging a transistor beyond repair?Not learned 95. A voltage amplifier has a calculated voltage gain of 5. Which statement is true concerning input and output voltages?Not learned 96. How are operational amplifiers, used primarily in analog circuits, characterized?Not learned 97. As shown in all four diagrams included in the illustration, what type of logic circuit is representedNot learned 98. A bearing temperature monitoring system such as that used for measuring selected propulsion plant bearings uses what technology?Not learned 99. What statement is true concerning read only memory (ROM)?Not learned 100. 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?Not learned 101. 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?Not learned 102. In addition to SF6 gas circuit breakers, of the types listed below, what type of circuit breaker is used for high voltage practice aboard ship?Not learned 103. What is an ammeter used to measure?Not learned 104. In what applications are semiconductor diodes commonly used?Not learned 105. What application would the switchboard instrumentation panel shown in the illustration best be suited forNot learned 106. The arc resulting from the tripping of a circuit breaker is prevented from damaging the contacts. How is this done?Not learned 107. What is the basic similarity between a circuit breaker and a fuse?Not learned 108. When a battery-operated megohmmeter (insulation tester) is used to perform a dielectric absorption test, the resistance is measured and recorded from each conductor to ground each minute for 10 consecutive minutes. What condition accounts for a gradual rise in resistance each successive minute?Not learned 109. What can be the cause of excessive heat or burning contacts in an operating motor controller?Not learned 110. What is the characteristic that is associated with an "instantaneous-trip" single-element type fuse?Not learned 111. What does the circuit shown in the illustration representNot learned 112. A common type of molded case circuit breaker has both thermal and magnetic trip elements. If a branch circuit breaker has only thermal or magnetic trip elements (but not both), it is common to use multiple series-connected protective devices to provide both short-circuit and overload protection. If a motor branch circuit is protected with both a thermal trip-type circuit breaker and fuses, what is the protective purpose of the fuses used in this arrangement?Not learned 113. The component labeled "CR1" in the circuit shown in the illustration serves what functional purposeNot learned 114. Concerning the illustrated fire detection and alarm system, when the system is operating normally and under supervision, what is the status of the ground detector and the fire alarm relaysNot learned 115. If the cooling water system is isolated for repairs, but in an operational emergency, it is still desirable to run the alternator pictured in figure "A" of the illustration, what must be doneNot learned 116. If a digital multimeter set up to measure AC volts reads low value, but constantly changing "ghost voltages" when its leads are disconnected, what does this indicate?Not learned 117. If a digital multimeter is setup as shown in figures "A" and "B" of the illustration, what is the status of the silicon diode if the display reads 4.7 ohms when configured as in figure "A" and reads 490 ohms when configured as in figure "B"Not learned 118. Which electrical schematic symbol shown in the illustration represents a thermostat which opens on rising temperatureNot learned 119. Which figure represents the schematic symbol shown in figure "2"Not learned 120. In which of the following branch circuits types would time lag fuses (or dual-element fuses) be MOST likely used?Not learned 121. Which of the following illustrated manual motor starters represents the wiring diagram illustrated in figure "A"Not learned 122. Which of the following pictures represents a magnetic reversing or two-speed motor starterNot learned 123. Which of the following statements concerning figure "6" of the illustration is trueNot learned 124. Which of the following statements concerning nickel-cadmium batteries is true?Not learned 125. Which of the following statements is true concerning step-down transformer operation?Not learned 126. What is the functional purpose of a generic electromagnetic relay?Not learned 127. What is the functional purpose of the Zener diode "CR1" as shown in section "D" of the regulated DC power supplyNot learned 128. When regreasing the electric motor bearing as shown in figure "B" of the illustration, what practice should be avoidedNot learned 129. In the illustration of the one-line distribution system diagram, if at sea the 450 VAC section of the main switchboard experiences a complete loss of power, what statement is true concerning the operation of the emergency diesel-generatorNot learned 130. In the illustration, 1, 2, 3 and 4 are 12-volt batteries. What will be the nominal voltage as read by a voltmeter across the output of the battery bankNot learned 131. Large machines undergoing a resistance insulation testing using a megohmmeter should be discharged to remove any accumulated electrostatic/capacitive/dielectric-absorption charge stored. When should this discharge be performed?Not learned 132. The motor of the illustrated motor controller fails to start on an attempted startup. You ensure the motor has not tripped out on overload, and you check the disconnect switch closed. With the start button depressed, a voltmeter reading between 3 and 4, as in figure "A" shown in the illustration, indicates line voltage. After re- opening the disconnect switch and verifying the circuit de-energized, what should be your next step in the troubleshooting processNot learned 133. If the motor shown in the illustration will not start when the "off-run" switch is placed in the run position, which of the listed components should be checked FIRSTNot learned 134. What is the name of the component labeled CR1 as shown in section "D" of the regulated DC power supply illustratedNot learned 135. What is the name of the device that works in conjunction with an automatic voltage regulator and is used as the source of magnetizing direct current delivered to the rotating field of an AC generator?Not learned 136. What is the name of the semiconductor device with the essential characteristic that it decreases in resistance with an increase in temperature?Not learned 137. Why are nickel-cadmium batteries superior to lead-acid batteries for standby service?Not learned 138. If overloading an electric motor becomes necessary in an emergency situation, what should be done to prevent damage to the motor while allowing sustained operation?Not learned 139. Which pair of safety disconnect switches shown in the illustration represents the exterior and interior views of a double-throw switchNot learned 140. What is the primary means by which an electrical maintenance worker is protected from electrical hazards while performing work on an electrical circuit?Not learned 141. After prior isolation and lock-out/tag-out procedures are performed, which electrical device requires discharging any stored electrical energy before any work may safely begin?Not learned 142. The propulsion motor most often utilized in an AC drive system operating in the moderate to high power range is of what type?Not learned 143. What is a purpose of the automatic bus transfer device shown in the illustrationNot learned 144. What is the purpose of an electromagnetic relay?Not learned 145. What is the purpose of a three-phase lighting power transformer bank of a shipboard distribution system?Not learned 146. Referring to figure "3" of the illustration, what type of logic gate is symbolizedNot learned 147. In referring to figure "E" of the illustration, what statement is true concerning the functional purpose of the coupling transformerNot learned 148. Referring to the illustration pertaining to an alternator protection and alarm system, what statement is true concerning the component labeled "LO"Not learned 149. Referring to the illustration pertaining to the semi-automatic navigation light panel circuit, if the buzzer sounds and the masthead indicator light comes on, what statement is true concerning acknowledging and responding to the alarm while minimizing the danger to navigationNot learned 150. Referring to the illustration, what is the position of the three circuit breakers labeled in figure A, B, and C respectivelyNot learned 151. Referring to the impressed current cathodic hull protection system shown in the illustration, if required to control the impressed current to the anodes manually by using the hand adjustment potentiometer, what parameter should be maintained at a constant valueNot learned 152. Referring to the sound-powered telephone circuit shown in the illustration, what statement is trueNot learned 153. What is the most reliable and preferred method for determining the state of charge of a wet cell NiCad battery while it is being charged?Not learned 154. As shown in the cutaway view of the lead-acid battery in figure "A" of the illustration, if one-half of the battery's cells are revealed by the cutaway section (with the other half remaining hidden from view), what is the nominal output voltage of the batteryNot learned 155. As shown in figure "6" of the illustration, what does the symbol represent as used in electrical drawingsNot learned 156. As shown in figures "A", "B", "C", and "D" of the illustration, what is the usual means by which the rotation direction of the motor is reversedNot learned 157. As shown in figure "A" of the illustration, what does the M-G set's three-phase drive motor mechanically driveNot learned 158. As shown in figure "A" of the digital multimeter screen shown in the illustration, what would be the significance of the symbol indicated by "1" being illuminatedNot learned 159. As shown in figure "A" of the illustrated propulsion motor variable speed drive, what statement is trueNot learned 160. As shown in figure "A" of the illustration, the load-commutated inverter drive illustrated has how many pulsesNot learned 161. As shown in figure "A" of the illustration, with the switch closed what statement is true if "R1" and "R2" have unequal resistance valuesNot learned 162. As shown in the illustrated block diagram for a distributed automation system, what statement is true concerning the units labeled "ROS" which are remote operating system workstationsNot learned 163. As shown in the illustrated block diagram for a distributed automation system, what statement is true concerning the workstations labeled "LOS" associated with the port power management systemNot learned 164. As shown in the illustrated devices and symbols, which of the symbols shown in the illustration represents a standard normally closed relay contactNot learned 165. As shown in the illustrated diagnostic setup for locating a shorted field coil of a ten-pole synchronous motor, if 240 VAC/60 Hz is applied across the brushes, what would be the individual voltage drops measured across each field coil assuming that none of the field coils are shortedNot learned 166. As shown in the illustrated feeder disconnect controller, what statement is trueNot learned 167. As shown in the illustrated plots of uncorrected and temperature corrected insulation resistance readings for a particular piece of equipment, at what point in time should the equipment have been refurbished or replacedNot learned 168. As shown in the illustrated wound-rotor induction motor, what statement is true concerning motor lead connectionsNot learned 169. As shown in the illustration, which of the following pieces of equipment is supplied with a circuit breaker providing both overload and short-circuit protectionNot learned 170. As shown in all three diagrams included in the illustration, what type of logic circuit is representedNot learned 171. While standing an "at sea watch" onboard an AC diesel-electric drive ship with a synchronous propulsion motor with the ability to vary the field excitation strength and still remain in synchronism. Ideally what would be the character of the power factor associated with the main power distribution system including all motors?Not learned 172. What statement is true concerning the electrical diagrams for the motor controller shown in the illustrationNot learned 173. If the supply voltage is 220 volts 60 Hz, what is the operating voltage of the motor controller control circuit illustrated in figure "A" of the illustrationNot learned 174. Suppose it is desired to connect a dual voltage three-phase squirrel-cage induction motor for low volts, but it is undetermined whether the nine-lead motor is internally configured for wye or delta configuration. Using an ohmmeter, the motor itself with leads disconnected, and the illustration as a guide, what statement is trueNot learned 175. Suppose an ungrounded 3-phase distribution system is fitted with a lamp-type ground detecting circuit with 3 lamps. If an accidental ground is displayed continuously, what is the indication on the switchboard of a single grounded conductor?Not learned 176. A thermal-magnetic molded case circuit breaker for a 300 kW alternator is rated at 500 amperes at full continuous load. Which of the following conditions will MOST likely trip the breaker?Not learned 177. The torque-speed and current-speed curves for a three-phase induction motor with a squirrel-cage rotor are shown in figures "A" and "B" of the illustration. Which of the following statements is true concerning the depicted curvesNot learned 178. What type of electrical diagram for the autotransformer type motor controller is shown in the illustrationNot learned 179. What type of electrical diagram for the electrical distribution system is shown in the illustrationNot learned 180. Using the temperature correction factor for the winding insulation temperature graph shown in the illustration, what would be the correction factor and the corrected temperature to 40 degrees C for a motor with an insulation resistance of 4 megohms measured at 50 degrees CNot learned 181. Which of the wave shapes shown in the illustration is termed a sinusoidal waveNot learned 182. Which of the following statements is correct for the illustrated circuit in figure "B"Not learned 183. When configuring a digital multimeter as an ohmmeter, what will MOST likely be displayed on the screen when the test leads are shorted together?Not learned 184. If a digital multimeter is set up as shown in figures "A" and "B" of the illustration, what is the status of the silicon diode if the display reads 5 megohms when configured as in figure "A" and the display reads infinite (OL) megohms when configured as in figure "B"Not learned 185. Which of the electronic schematic symbols represents the capacitor illustrated in figure "1" of the illustrationNot learned 186. As shown in the illustrated harmonic analysis diagram, which figure represents the fundamental (or first harmonic)Not learned