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1 U.S.C.G. Merchant Marine Exam Third Assistant Engineer Q536 Electrical-Electronic-Control Engineering (Sample Examination) 9/10/2018 Page 1 of 42

2 U.S.C.G. Merchant Marine Exam Third Assistant Engineer Q536 Electrical-Electronic-Control Engineering Illustrations: 23 Choose the best answer to the following Multiple Choice Questions. 1. In figure "4" of the diagram in the illustration, the three-phase step-down power transformer has a turns ratio of five to one. If a three-phase 4160 volt supply is connected to terminals "A1-B1-C1", what voltage should develop across terminals "A2-B2-C2"? Illustration EL-0084 o (A) 240 volts o (B) 415 volts (C) 480 volts o (D) 832 volts If choice C is selected set score to 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"? Illustration EL-0211 o (A) the diode is shorted o (B) the diode is open (C) the diode is functioning properly o (D) the diode is intermittently open If choice C is selected set score to An open primary coil in a voltage transformer (VT) will be indicated by which of the listed conditions? (A) No voltage on the output of the secondary coil. o (B) An infinite resistance value on the secondary coil. o (C) Low resistance value on the primary coil. o (D) Overloaded secondary coil. If choice A is selected set score to To keep emergency lead-acid batteries in a full state of charge for emergency use, what is normally done? o (A) Batteries are kept charged by cycling through discharge and charge cycles daily. o (B) Batteries are kept charged by performing an equalizing charge daily. o (C) Batteries are kept charged by maintaining the maximum charging rate. (D) Batteries are kept charged by maintaining a continuous trickle charge. 9/10/2018 Page 2 of 42

3 U.S.C.G. Merchant Marine Exam Third Assistant Engineer Q536 Electrical-Electronic-Control Engineering Illustrations: As shown in figure "A" of the illustrated motor nameplate, how much current could the motor safely draw on a continuous basis at sea level without overheating? Illustration EL-0171 o (A) 142 amps o (B) 156 amps o (C) 163 amps (D) 187 amps 6. Assuming that a three-phase synchronous motor is separately excited, what statement is true concerning power supplies? o (A) The rotor winding via slip rings and brushes is connected to a single phase AC power source, and the stator winding is directly connected to a three-phase AC power source. o (B) The rotor winding via slip rings and brushes is connected to a three-phase AC power source, and the stator winding is directly connected to a single phase AC power source. o (C) The rotor windings via slip rings and brushes are connected to a three-phase AC power source, and the stator winding is directly connected to a DC power source. (D) The rotor winding via slip rings and brushes is connected to a DC power source, and the stator windings are directly connected to a three-phase AC power source. 7. From the information given in the illustration, which of the following statements is correct? Illustration EL-0106 o o o (A) The emergency generator is capable of being connected directly to the main 480 VAC bus. (B) Shore power, in port, is only capable of feeding emergency loads. (C) It is possible for the main-emergency bus-tie circuit breaker and the emergency generator circuit breaker to be simultaneously closed. (D) During normal operation, the main-emergency bus-tie circuit breaker and any on-line ship's service generator circuit breakers are simultaneously closed. 8. Regulations require that shipboard cabling use stranded copper conductors. Why is copper a superior conductor compared to aluminum? (A) Even though copper is heavier in weight than aluminum, copper has less resistance than aluminum. o (B) Even though copper is lower in conductivity than aluminum, copper has more resistance than aluminum. o (C) Even though copper is more corrosive than aluminum, copper is lighter in weight than aluminum. o (D) Even though copper has more resistance than aluminum, copper is lighter in weight than aluminum. If choice A is selected set score to 1. 9/10/2018 Page 3 of 42

4 U.S.C.G. Merchant Marine Exam Third Assistant Engineer Q536 Electrical-Electronic-Control Engineering Illustrations: What will happen to the total effective circuit resistance when additional parallel circuits are added to a circuit? o (A) it will decrease, causing an increase in the line voltage o (B) it will increase, causing a drop in the total load current o (C) it will increase, causing a decrease in the line voltage (D) it will decrease, causing an increase in the total load current 10. What is the shape of the schematic symbol for an operational amplifier used in an analog circuit? o (A) square (B) triangle o (C) circle o (D) trapezoid If choice B is selected set score to What would be the total current draw of the circuit as shown in figure "A" of the illustration if the source voltage is 24 volts, the resistance for R1 is 12 ohms, the resistance for R2 is 24 ohms, and the resistance for R3 is 36 ohms? Illustration EL-0032 o (A) 0.33 amperes o (B) 0.75 amperes o (C) 1.25 amperes (D) 1.33 amperes 12. What type of electrical diagram for the electrical distribution system is shown in the illustration? Illustration EL-0014 (A) The diagram is a one-line diagram. o (B) The diagram is an isometric diagram. o (C) The diagram is a ladder or line diagram (schematic). o (D) The diagram is a wiring diagram. If choice A is selected set score to When a resistor is used as a shunt and is connected in parallel with an analog meter movement coil, what capability does this provide? o (A) measuring of circuit resistance live (B) extending the range of the meter current o (C) increasing accuracy of approximately 1.5 percent o (D) this is never done If choice B is selected set score to 1. 9/10/2018 Page 4 of 42

5 U.S.C.G. Merchant Marine Exam Third Assistant Engineer Q536 Electrical-Electronic-Control Engineering Illustrations: To properly use a clamp-on-type ammeter for measuring current accurately, what must be done? o (A) Enclose multiple conductors within the jaws AND make sure the jaws are open. o (B) Enclose multiple conductors within the jaws AND make sure the jaws are closed. o (C) Enclose one conductor within the jaws AND make sure the jaws are open. (D) Enclose one conductor within the jaws AND make sure the jaws are closed. 15. When configuring a digital multimeter as an ohmmeter, what will MOST likely be displayed on the screen when the test leads are shorted together? o (A) A reading of "OL" ohms will be displayed. o (B) A reading of residual test lead and internal resistance will be displayed (typically.2 to.5 ohms). o (C) A reading of 0 ohms will be displayed. (D) B or C could be correct depending upon the digital multimeter. 16. 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? (A) The insulation is in good condition. o (B) The insulation is contaminated with moisture. o (C) The insulation is cracked and otherwise deteriorated. o (D) The insulation has direct continuity with ground. If choice A is selected set score to 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? o (A) The specific gravity of the electrolyte will decrease as only the sulfuric acid will evaporate from the electrolyte solution. o (B) Although the specific gravity will change due to evaporation, there is no predictable tendency either way. o (C) The specific gravity of the electrolyte will remain unchanged as both the water and sulfuric acid will evaporate from the electrolyte solution. (D) The specific gravity of the electrolyte will increase as only the water will evaporate from the electrolyte solution. 9/10/2018 Page 5 of 42

6 U.S.C.G. Merchant Marine Exam Third Assistant Engineer Q536 Electrical-Electronic-Control Engineering Illustrations: 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 shorted? Illustration EL o (A) 6 VAC o (B) 12 VAC (C) 24 VAC o (D) 48 VAC If choice C is selected set score to What can be the cause of excessive heat or burning contacts in an operating motor controller? (A) dirty or pitted contacts o (B) low motor starting torque o (C) burned out operating coil o (D) high ambient temperature If choice A is selected set score to From the information given in the illustration, what would be the ampere capacity at full load of each of the main ship service diesel-generators if operating at the rated power factor of 0.8? Illustration EL-0106 o (A) 2500 amps (B) 3011 amps o (C) 4325 amps o (D) 5208 amps If choice B is selected set score to How can the loss of residual magnetism in an alternator with a brushless excitation system be corrected? (A) using a storage battery or battery charger to "flash" the field o (B) running the rotor in the opposite direction for 5 minutes o (C) running the generator at normal speed with the field rheostat fully counter-clockwise o (D) allowing the generator to run at 10% of normal speed for 5 minutes If choice A is selected set score to 1. 9/10/2018 Page 6 of 42

7 U.S.C.G. Merchant Marine Exam Third Assistant Engineer Q536 Electrical-Electronic-Control Engineering Illustrations: 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? o (A) Measuring the specific gravity of each cell with a hydrometer. (B) Measuring the battery voltage with a digital voltmeter. o (C) Measuring the battery voltage with a solenoid type voltage tester. o (D) Measuring the temperature corrected specific gravity of each cell with a hydrometer and thermometer. If choice B is selected set score to How is the difference between the synchronous speed of a three-phase induction motor and its operating speed correctly expressed? o (A) deviation o (B) a decimal fraction of full load speed (C) slip o (D) a percent of full load speed If choice C is selected set score to What type of AC motor would use a rheostat in the rotor circuit to vary the speed of the motor? o (A) synchronous motor (B) wound-rotor induction motor o (C) squirrel-cage induction motor o (D) regenerative braking motor If choice B is selected set score to What is the function of the movable cams in a master-switch winch motor drum controller? o (A) limit the amount of load put on the motor (B) regulate the speed of the motor o (C) insulate the operating handle o (D) maintain resistance contacts in clean condition If choice B is selected set score to Concerning the illustrated motor controller circuit, where is the location of the motor "run" indicator light? Illustration EL-0004 o (A) At the local control station. o (B) At the motor. o (C) There is no motor "run" light. It is, instead, a motor "stopped" light. (D) At the remote operating station. 9/10/2018 Page 7 of 42

8 U.S.C.G. Merchant Marine Exam Third Assistant Engineer Q536 Electrical-Electronic-Control Engineering Illustrations: As shown in the illustration of an electrically operated watertight door controller, how is reversal of the direction of motor rotation achieved? Illustration EL-0115 o (A) The shunt field windings are reversed. (B) The armature windings are reversed. o (C) The series field windings are reversed. o (D) Both the series field and armature windings are reversed. If choice B is selected set score to Diesel-generators #1 and #2 are operating in parallel with each machine operating at half-capacity. Diesel-generator #1 suddenly trips out mechanically due to low lube oil pressure. The reverse power relay functions properly and trips generator #1 electrically off the board. In the absence of an automated power management system, which of the following actions should you carry out FIRST? o (A) Secure alarms, reset reverse power relay, and restart #1 engine. o (B) Start the emergency generator. (C) Strip the board of all nonvital circuits. o (D) Ascertain cause of the low lube oil pressure. If choice C is selected set score to 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? o (A) alternator (B) exciter o (C) governor o (D) magnetizer If choice B is selected set score to 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? o (A) Sustained current draw of 450 amperes indefinitely. o (B) Sustained current draw of 500 amperes for 3 hours. o (C) Momentary current draw of 1000 amperes for 3 seconds. (D) Instantaneous current draw of 10,000 amperes for.03 seconds. 9/10/2018 Page 8 of 42

9 U.S.C.G. Merchant Marine Exam Third Assistant Engineer Q536 Electrical-Electronic-Control Engineering Illustrations: Incandescent lamps are classified according to the shape of the bulb and the type of service, as well as the size and style of the base. How are incandescent lamps rated? o (A) operating reactance o (B) operating frequency and impedance (C) operating voltage and wattage o (D) operating resistance If choice C is selected set score to Referring to the containership one-line distribution diagram shown in the illustration, what is the purpose of the feedback circuit breaker as used to bypass the automatic bus transfer device? Illustration EL-0014 o (A) It allows the emergency generator to be paralleled with the ship's service generators when additional power is needed. o (B) Since it is normally closed, it is the means by which the emergency generator control circuit senses the voltage at the emergency bus. o (C) Since it is normally closed, it is the means by which the emergency generator control circuit senses the voltage at the main bus. (D) It allows the emergency generator to feed the main bus during dead ship start-up; otherwise it is generally open and not used. 33. As shown in the illustrated harmonic analysis diagram, which figure represents the fundamental (or first harmonic)? Illustration EL-0163 o (A) A (B) B o (C) C o (D) D If choice B is selected set score to Which of the following statements correctly applies to bipolar junction transistors? o (A) LED and LCD are the two basic types of transistors. o (B) The emitter separates the base and collector. (C) The three terminals are called the emitter, base, and collector. o (D) The collector separates the emitter and base. If choice C is selected set score to 1. 9/10/2018 Page 9 of 42

10 U.S.C.G. Merchant Marine Exam Third Assistant Engineer Q536 Electrical-Electronic-Control Engineering Illustrations: A common-emitter circuit has an input voltage of 0.1 volt, an output voltage of 2.0 volts, an input current of 0.5 milliamps, and an output current of 10 milliamps. What is the power gain? o (A) 20 o (B) 40 (C) 400 o (D) 4000 If choice C is selected set score to In referring to figure "A" of the illustration, what type of active filter circuit is shown? Illustration EL (A) Low-pass filter circuit o (B) Bandpass filter circuit o (C) Notch filter circuit o (D) High-pass filter circuit If choice A is selected set score to As shown in all four diagrams included in the illustration, what type of logic circuit is represented? Illustration EL-0234 (A) NOR gate o (B) NAND gate o (C) AND gate o (D) OR gate If choice A is selected set score to Of the following, what shipboard system is MOST likely to use the synchronous transmission system featuring a transmitter and receiver? o (A) Turbocharger RPM indicator system o (B) Centrifuge RPM indicator system o (C) Shaft revolution indicator system (D) Rudder angle indicator system 9/10/2018 Page 10 of 42

11 U.S.C.G. Merchant Marine Exam Third Assistant Engineer Q536 Electrical-Electronic-Control Engineering Illustrations: 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 workstations? Illustration EL o (A) The ROS located in the ship's office is designated as the master ROS. o (B) The ROS located in the wheelhouse is designated as the master ROS. o (C) Operator access to control functions among the various ROS locations are all identical. (D) Operator access to control functions among the various ROS locations differ depending system configuration and need. 40. What Ethernet cabling technology supports the greatest data transfer speeds? o (A) Fast Ethernet o (B) Thick Ethernet o (C) Thin Ethernet (D) Gigabit Ethernet 41. 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 value? Illustration EL-0090 o (A) Individual anode currents (B) Reference electrode voltage o (C) Control amplifier output voltage o (D) Total anode current If choice B is selected set score to 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 system? Illustration EL-0092 o (A) gear transmission o (B) differential gear o (C) telemotor (D) synchro transmitter and receiver 9/10/2018 Page 11 of 42

12 U.S.C.G. Merchant Marine Exam Third Assistant Engineer Q536 Electrical-Electronic-Control Engineering Illustrations: Which of the following methods should be used to dress the face of silver-plated contacts? (A) Sanding with 400 grit sandpaper o (B) Burnishing with a burnishing tool o (C) Filing with a mill file o (D) Knurling with a knurling tool If choice A is selected set score to You are replacing a three-phase induction motor in an application where equipment could be damaged if the direction of rotation of the motor is incorrect when connected. Assuming that even momentarily jogging the motor could damage equipment and that the feeder phase sequence is ABC clockwise as tested with a phase sequence indicator, what should then be done to ensure that the motor rotation will be correct (clockwise) when connected electrically to the line and mechanically to the load? Assume that the power is off and that the contact-type motor rotation indicator leads are connected to the motor terminals. o o (A) Rotate the shaft by hand in the clockwise direction as viewed from the drive end. With the push to test pushbutton depressed, if the sequence indicates ABC, phase sequence and motor rotation are NOT in agreement and any two leads must be interchanged. (B) Rotate the shaft by hand in the clockwise direction as viewed from the drive end. With the push to test pushbutton depressed, if the sequence indicates ACB, phase sequence and motor rotation are in agreement and no connection changes are necessary. (C) Rotate the shaft by hand in the clockwise direction as viewed from the drive end. With the push to test pushbutton depressed, if the sequence indicates ABC, phase sequence and motor rotation are in agreement and no connection changes are necessary. o (D) Rotate the shaft by hand in the clockwise direction as viewed from the drive end. With the push to test pushbutton depressed, if the sequence indicates ACB, phase sequence and motor rotation are NOT in agreement and all three leads must be interchanged. If choice C is selected set score to Why must caution be exercised during the charging of flooded lead-acid storage batteries? o (A) lead peroxide in the negative plate is poisonous o (B) both plates are changing chemically to lead sulfate o (C) the acid will become weaker (D) hydrogen gas can be liberated during charging 9/10/2018 Page 12 of 42

13 U.S.C.G. Merchant Marine Exam Third Assistant Engineer Q536 Electrical-Electronic-Control Engineering Illustrations: 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? o (A) The alternator output voltage must be maintained at the rated value for the alternator output voltage. (B) The alternator output voltage must be decreased proportionately downward with the o frequency decrease. (C) The alternator output voltage must be increased proportionately upward to compensate for the frequency decrease. o (D) Under no circumstances is it permissible to run an alternator at a frequency lower than 5% below its rated frequency. If choice B is selected set score to Before electrical work can be safely undertaken, the equipment must be de-energized, locked and tagged out, and verification must be made that the circuit is actually dead. What testing device is most certain to reliably verify that a circuit is actually dead? o (A) a non-autoranging digital multimeter (B) an autoranging digital multimeter o (C) a solenoid type voltage tester o (D) a non-contact voltage tester If choice B is selected set score to In accordance with 46 CFR Subchapter J (Electrical Engineering), on vessels equipped with both temporary and final emergency power sources, emergency generators are required to automatically start upon a loss of normal supply voltage. When the potential of the normal source is eventually restored, what statement is true? o (A) The emergency loads must be manually transferred to the normal source, and the emergency generator must be manually stopped. o (B) The emergency loads must be configured to automatically transfer to the normal source, and the emergency generator must be configured to automatically stop. (C) The emergency loads must be either manually or automatically transferred to the normal source, and the emergency generator must be manually or automatically stopped. o (D) The emergency loads must be configured to automatically transfer to the normal source, and the emergency generator must be manually stopped. If choice C is selected set score to Which statement is TRUE concerning electric propulsion drives? o (A) Lower transmission losses compared to other types of propulsion drives. o (B) Lack of flexibility of arrangement between the prime mover and motor. (C) The propeller speed and direction of rotation are easily controllable. o (D) Inability to be utilized as a source of ships service power. If choice C is selected set score to 1. 9/10/2018 Page 13 of 42

14 U.S.C.G. Merchant Marine Exam Third Assistant Engineer Q536 Electrical-Electronic-Control Engineering Illustrations: By what common means is the speed of an AC propulsion motor on a diesel-electric propulsion ship controlled? (A) by varying both the input frequency and voltage to the motor o (B) by varying the input voltage to the motor, but not the frequency o (C) by varying the input frequency to the motor, but not the voltage o (D) by varying either the input voltage or frequency to the motor, but not both If choice A is selected set score to 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? o (A) The live-line tester should be checked by connecting to a known high voltage source only after testing the circuit to be worked upon. (B) The live-line tester should be checked by connecting to a known high voltage source before and after the circuit to be worked upon is tested. o (C) The live-line tester should be checked by connecting to a known high voltage source only before testing the circuit to be worked upon. o (D) The live-line tester need not be checked prior to testing the circuit to be worked upon as long as it has not been declared inoperative. If choice B is selected set score to 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? o (A) To completely eliminate ground fault current (B) To minimize the magnitude of the ground fault current o (C) To maximize the magnitude of the ground fault current o (D) To prevent nuisance ground fault trips If choice B is selected set score to In a podded azimuthing propulsion system, how is three-phase, frequency and voltage controlled power delivered to the synchronous propulsion motor stator windings? o (A) By the use of commutator bars and brushes. o (B) By rotary transformer action. o (C) By direct connection to the stator windings. (D) By the use of slip rings and brushes. 9/10/2018 Page 14 of 42

15 U.S.C.G. Merchant Marine Exam Third Assistant Engineer Q536 Electrical-Electronic-Control Engineering Illustrations: Referring to the sound-powered telephone circuit shown in the illustration, what statement is true? Illustration EL-0093 o (A) The sound-powered telephone circuitry consists of a selective-talk circuit and a commonringing circuit. o (B) The sound-powered telephone circuitry consists of selective-talk and selective-ringing circuits. o (C) The sound-powered telephone circuitry consists of common-talk and common-ringing circuits. (D) The sound-powered telephone circuitry consists of a common-talk circuit and a selectiveringing circuit. 55. When testing insulation resistance of electric equipment and machinery, ideally when should the insulation resistance be tested for the lowest normal insulation values? o (A) every 30 days whether the machine is in use or not o (B) every time the brush rigging is adjusted o (C) immediately after starting up the machine (D) immediately after shutting down the machine 56. When a fluorescent lamp has reached the end of its useful life, it should be replaced immediately. If not, what condition could the resultant flashing cause? o (A) tripping of the lamp's circuit breaker (B) damaging the lamp's ballast circuit o (C) exploding of the lamp, causing glass to fly in all directions o (D) short circuiting of adjacent lighting circuits If choice B is selected set score to In terms of the type of load in an alternating circuit, in what type of alternating current circuit will the voltage always lead the current? o (A) resistive circuit o (B) capacitive circuit (C) inductive circuit o (D) resistive-capacitive circuit If choice C is selected set score to 1. 9/10/2018 Page 15 of 42

16 U.S.C.G. Merchant Marine Exam Third Assistant Engineer Q536 Electrical-Electronic-Control Engineering Illustrations: What is the total effective resistance of figure "B" of the illustrated circuit if the resistance of R1 is 3 ohms, R2 is 4 ohms, and R3 is 5 ohms? Illustration EL-0020 o (A) 0.5 ohms o (B) 1.28 ohms o (C) 1.5 ohms (D) 12 ohms 59. As shown in figure "A" of the illustration, what would be the circuit impedance if the capacitive reactance is 10 ohms and the resistance is 10 ohms? Illustration EL-0109 o (A) 4.47 ohms capacitive o (B) 6.32 ohms capacitive (C) ohms capacitive o (D) 20 ohms capacitive If choice C is selected set score to What would be the actual rotor speed for a 4-pole three-phase squirrel-cage induction motor operating at 60 Hz if the rotor slip is 3%? (A) 1746 RPM o (B) 1793 RPM o (C) 1800 RPM o (D) 1854 RPM If choice A is selected set score to Refer to the simplified diagram of the AC synchronous electric motor drive system as shown in the illustration. The propulsion motor operates from maneuvering speed to full ahead speed in the ahead direction. The propulsion motor will not operate at any speed in the astern direction. What is most likely the problem? Illustration EL-0155 o (A) The AC propulsion motor has an open astern winding. o (B) Due to a controller fault, the power supply to the controlled rectifier fails to achieve a phase sequence reversal. (C) Due to a controller fault, the output of the controlled inverter fails to achieve a reversal in phase sequence. o (D) The AC propulsion motor field winding fails to reverse in polarity. If choice C is selected set score to 1. 9/10/2018 Page 16 of 42

17 U.S.C.G. Merchant Marine Exam Third Assistant Engineer Q536 Electrical-Electronic-Control Engineering Illustrations: The winch shown in the illustration operates in any of the positions with the master switch in the 'lower' direction, but will not 'hoist' in any of the master switch hoist speed positions. Which of the listed faults would MOST likely be the cause? Illustration EL-0102 o (A) The undervoltage relay contacts between terminals 1 and 2 have failed open. o (B) The AC hoist motor has tripped out on overload, permitting only lowering. (C) The hoist limit switch (LSH) contacts across terminals 9 and 10 have failed open. o (D) The lower limit switch (LSL) contacts across terminals 5 and 6 have failed open. If choice C is selected set score to Within the split-phase family of single phase motors, what are the operational characteristics of the motor shown in figure "A" of the illustration? Illustration EL-0207 o (A) Relatively high starting torque with power factor correction (B) Relatively low starting torque with no power factor correction o (C) Relatively high starting torque with no power factor correction o (D) Relatively low starting torque with power factor correction If choice B is selected set score to In which of the following branch circuits types would time lag fuses (or dual-element fuses) be MOST likely used? o (A) general alarm circuits o (B) main lighting circuits (C) motor starting circuits o (D) emergency lighting circuits If choice C is selected set score to Which of the listed figures shown in the illustration represents a three-phase transformer connected in a wye-wye configuration? Illustration EL-0084 o (A) 1 (B) 2 o (C) 3 o (D) 4 If choice B is selected set score to 1. 9/10/2018 Page 17 of 42

18 U.S.C.G. Merchant Marine Exam Third Assistant Engineer Q536 Electrical-Electronic-Control Engineering Illustrations: In the diagram of the switchboard shown in the illustration, what is the purpose of the current transformers? Illustration EL-0003 o o o (A) transform relatively low generator load current to high instrument input current for voltmeters (B) transform relatively high generator load current to low instrument input current for voltmeters (C) transform relatively low generator load current to high instrument input current for ammeters, wattmeters, and the power factor meter (D) transform relatively high generator load current to low instrument input current for ammeters, wattmeters, and the power factor meter 67. What type of motor is generally used in DC propulsion drive systems? o (A) differentially compounded o (B) permanent magnet o (C) series-wound (D) shunt-wound or separately excited 68. Referring to the illustration pertaining to an alternator protection and alarm system, what statement is true concerning the component labeled "LO"? Illustration EL-0067 (A) LO is an alternator electrical fault trip master lock-out and alarm device. o (B) LO is an alternator phase loss safety shutdown and alarming device. o (C) LO is an alternator prime mover low lube oil pressure safety shutdown and alarming device. o (D) LO is an alternator bearing low lube oil pressure safety shutdown and alarming device. If choice A is selected set score to In actual applications, electrical connections associated with "R1, R2 and R3" of the transmitter to "R1, R2, and R3" of the indicators shown in figure "C" of the illustration are made by what means? Illustration EL-0092 o (A) spliced and taped connections o (B) soldered contacts (C) slip rings and brushes o (D) solderless crimp-on connectors If choice C is selected set score to 1. 9/10/2018 Page 18 of 42

19 U.S.C.G. Merchant Marine Exam Third Assistant Engineer Q536 Electrical-Electronic-Control Engineering Illustrations: Which of the following statements, concerning the cleaning maintenance of a brushless generator, is correct? o (A) Hot soapy water should be used to remove dust and grime from windings. (B) Cleaning of windings should be performed on a conditional basis using a vacuum or using a clean, dry, lint-free rag. o (C) Cleaning of windings should be performed on a periodic basis regardless of the state of cleanliness. o (D) High-pressure air should be used to blow out dust and grime from the windings. If choice B is selected set score to 1. 9/10/2018 Page 19 of 42

20 EL /26/2017 Adapted for testing purposes only from HUBERT, Operating, Testing and Preventive Maintenance of Electrical Power Apparatus. Copyright 2003 Pearson Education Further reproduction prohibited without permission Page 20 of 42

21 EL-0004 Adapted for testing purposes only from HALL, Practical Marine Electrical Knowledge, 2E 6/26/2017 Copyright 2003 Dennis T. Hall Further reproduction prohibited without permission Page 21 of 42

22 EL /7/2017 Adapted for testing purposes only from HUNT, Modern Marine Engineer s Manual, Volume II, Third Edition Copyright 2002 by Cornell Maritime Press, Inc. Further reproduction prohibited without permission Page 22 of 42

23 EL /11/2017 Adapted for testing purposes only from GROB, Basic Electronics, Fourth Edition Copyright 1977 by McGraw-Hill, Inc. Further reproduction prohibited without permission Page 23 of 42

24 EL /7/2017 Adapted for testing purposes only from GROB, Basic Electronics, Fourth Edition Copyright 1977 by McGraw-Hill, Inc. Further reproduction prohibited without permission Page 24 of 42

25 EL-0067 Adapted for testing purposes only from HALL, Practical Marine Electrical Knowledge, 3 rd Edition Copyright 2014 by Dennis T. Hall 1/19/2018 Further reproduction prohibited without permission Page 25 of 42

26 EL /25/2018 Adapted for testing purposes only from KILIAN, Modern Control Technology, 3 rd Edition Copyright 2006 by Delmar, Cengage Learning Further reproduction prohibited without permission Page 26 of 42

27 EL /29/2018 Adapted for testing purposes only from HUBERT, Operating, Testing, and Preventive Maintenance of Electrical Power Apparatus Copyright 2003 by Pearson Education, Inc. Further reproduction prohibited without permission Page 27 of 42

28 EL-0090 Adapted for testing purposes only from HALL, Practical Marine Electrical Knowledge, 2 nd Edition Copyright 2003 by Dennis T. Hall 1/30/2018 Further reproduction prohibited without permission Page 28 of 42

29 EL /1/2018 Adapted for testing purposes only from SMITH, Modern Marine Electricity and Electronics Copyright 1966 by Cornell Maritime Press, Inc. Further reproduction prohibited without permission Page 29 of 42

30 EL /9/2018 Adapted for testing purposes only from HOSE-McCANN, Sound Powered Telephones Copyright 1964 by Hose-McCann Telephone Co. Further reproduction prohibited without permission Page 30 of 42

31 EL-0096 Adapted for testing purposes only from HUNT, Modern Marine Engineer s Manual, Volume II, 3 rd Edition Copyright 2002 by Cornell Maritime Press, Inc. 2/12/2018 Further reproduction prohibited without permission Page 31 of 42

32 EL /15/2018 Adapted for testing purposes only from HUBERT, Operating, Testing, and Preventive Maintenance of Electrical Power Apparatus Copyright 2003 by Pearson Education, Inc. Further reproduction prohibited without permission Page 32 of 42

33 EL-0106 One Line Distribution Diagram 2/16/2018 Adapted for testing purposes only from HARRINGTON, Marine Engineering Copyright 1992 by The Society of Naval Architects and Marine Engineers Further reproduction prohibited without permission Page 33 of 42

34 EL /20/2018 Adapted for testing purposes only Further reproduction prohibited without permission Page 34 of 42

35 EL-0115 Watertight Door Controller 2/27/2018 Adapted for testing purposes only from SMITH, Modern Marine Electricity and Electronics Copyright 1966 by Cornell Maritime Press, Inc. Further reproduction prohibited without permission Page 35 of 42

36 EL-0155 Adapted for testing purposes only from HALL, Practical Marine Electrical Knowledge, 3 rd Edition Copyright 2014 by Dennis T. Hall 3/22/2018 Further reproduction prohibited without permission Page 36 of 42

37 EL-0163 Adapted for testing purposes only from HALL, Practical Marine Electrical Knowledge, 3 rd Edition Copyright 2014 by Dennis T. Hall 4/18/2018 Further reproduction prohibited without permission Page 37 of 42

38 EL-0171 Standard Overload Relays General Instructions for Selection of Overload Relay Heater Elements: 1. Obtain full load current and service factor from motor nameplate of from motor manufacturer. Do not estimate full-load motor current from horsepower tables. 2. Determine if 1, 2, or 3 overload relays are needed. 3. Select proper heater from appropriate table according to class, size, type of enclosure and number of overload relays being used. Full load motor currents should be within the Min.-Max. ratings shown for the number of overload relays being used. 4. The tables apply only to standard, open type or totally enclosed fan-cooled, continuous duty motors (with a service factor of 1.15 and rated for 40 degrees C rise) in applications where motor and starter are located in the same ambient temperature. For applications of other motors with a service factor of 1, degrees C rise, totally enclosed non-ventilated, explosion proof, or for installations where ambient temperatures of motor and starter are different, refer to Chart A for selection of overload heater units. Motor continuous rating C rise 1.5 service factor 40 C rise 1.0 service factor C rise Heater Cat. No Chart A: Variations by Operating Conditions Ambient temperature same at starter and motor As specified from tables One size smaller than for 1.15 service factor as above Ambient temperature higher at starter than at motor One size larger than specified for each 15 C difference One size smaller than for 1.15 service factor as above Table 24: NEMA Size 6 for all Standard Enclosures Three Overload Relays per Starter Motor Current Min. Max. G30T G30T G30T G30T G30T Heater Cat. No Motor Current Min. Max. G30T G30T G30T G30T G30T Ambient temperature lower at starter than at motor One size smaller than specified for each 15 C difference One size smaller than for 1.15 service factor as above Heater Cat. No Motor Current Min. Max. G30T G30T G30T Adapted for testing purposes only from MAZUR, Troubleshooting Electric Motors, 4 th Edition Copyright 2010 by American Technical Publishers, Inc. 4/27/2018 Further reproduction prohibited without permission Page 38 of 42

39 EL /8/2018 Adapted for testing purposes only from HUBERT, Operating, Testing and Preventive Maintenance of Electrical Power Apparatus Copyright 2003 Pearson Education Further reproduction prohibited without permission Page 39 of 42

40 EL /8/2018 Adapted for testing purposes only from HUBERT, Operating, Testing and Preventive Maintenance of Electrical Power Apparatus Copyright 2003 Pearson Education Further reproduction prohibited without permission Page 40 of 42

41 EL /13/2018 Adapted for testing purposes only Further reproduction prohibited without permission Page 41 of 42

42 EL-0234 Relay and PLC Logic Compared Fig. A and B: Adapted for testing purposes only from HERMAN, Industrial Motor Control, 6 th Edition Copyright 2010 by Delmar, Cengage Learning Further reproduction prohibited without permission 6/13/2018 Fig. C and D: Adapted for testing purposes only from BOLTON, Programmable Logic Controllers, 5 th Edition Copyright 2009 by Elsevier Ltd. Further reproduction prohibited without permission Page 42 of 42