u.s.c.g. merchant marine exam qmed q802 … · duration of contact), contact with an energized...

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U.S.C.G. Merchant Marine Exam

QMED

Q802 Electrician

(Sample Examination)

of 25 Q802 Electrician

8/31/2017

U.S.C.G. Merchant Marine Exam QMED Q802 Electrician Illustrations: 9

Choose the best answer to the following Multiple Choice Questions.

1. When replacing a defective transformer in a paralleled transformer configuration, which of the following actions must be carried out to ensure proper operation of the equipment it serves?

o (A) The iron core of the transformer must be flashed to pre-magnetize it. • (B) The transformer connections must be made as before with regard to the indicated polarity. o (C) The secondary leads must be grounded for 10 minutes to remove static charges. o (D) The iron core must be grounded for 10 minutes to remove any residual magnetism.

If choice B is selected set score to 1.

2. 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?

o (A) DC systems • (B) 60 Hz AC systems o (C) 10 kHz AC systems o (D) All the above systems would be equally as damaging


3. Bleeding from a vein may be ordinarily controlled by __________.

o (A) heavy application of a disinfectant o (B) pinching the wound closed • (C) applying direct pressure to the wound o (D) pouring ice water directly into the wound

If choice C is selected set score to 1.

4. Which of the wave shapes shown in the illustration is termed a ramp or sawtooth wave? Illustration EL-0088

o (A) A o (B) B • (C) C o (D) E



8/31/2017

U.S.C.G. Merchant Marine Exam QMED Q802 Electrician Illustrations: 9 5. What causes the rotor of a synchronous motor to operate in synchronism with the rotating field?

• (A) the rotor is magnetically locked into step with the rotating magnetic field by the excitation current

o (B) the amortisseur (damper) windings o (C) the field strength varies directly with rotor slip o (D) the stator flux rotates in the opposite direction

If choice A is selected set score to 1.

6. The set point current at which a magnetic-type overload relay tends to trip may be increased by turning the dashpot in the "lower" direction. What effect will this action have?

o (A) increases magnetic force on the plunger and requires more current to trip the relay • (B) reduces magnetic force on the plunger and requires more current to trip the relay o (C) increases magnetic force on the plunger and requires less current to trip the relay o (D) reduces magnetic force on the plunger and requires less current to trip the relay


7. As shown in the illustrated wound-rotor induction motor, how is the direction of rotation of the motor reversed? Illustration EL-0148

• (A) Any two of the "T1, T2, and T3" leads are reversed only. o (B) Any two of the "M1, M2, and M3" leads are reversed only. o (C) Any two of the "T1, T2, and T3" leads are reversed and any of the two "M1, M2, and M3"

leads must be reversed as well. o (D) It is not possible to change the direction of rotation of a wound-rotor induction motor.


8. Which of the following devices would be forbidden to use as a primary means of electrical isolation?

• (A) start/stop push button station o (B) non-fused disconnect switch o (C) circuit breaker o (D) fused disconnect switch


9. In a single element cartridge-type fuse, what type of protection is provided for lighting and general power applications?

• (A) short-circuit protection using a fusible link o (B) sustained overload protection using a spring loaded soldered joint o (C) sustained overload protection using a fusible link o (D) short-circuit protection using a spring loaded soldered joint



8/31/2017

U.S.C.G. Merchant Marine Exam QMED Q802 Electrician Illustrations: 9 10. It is necessary to cool the bulkheads and decks surrounding a compartment where there is a fire in

order to __________.

o (A) cool the metal below its ignition temperature o (B) form a dense coating of smothering steam o (C) prevent oxygen from reaching the flames • (D) prevent the fire from spreading by the conduction of heat

If choice D is selected set score to 1.

11. A grinding wheel is trued with a __________.

• (A) dressing tool o (B) round file o (C) lathe tool o (D) garnet stone


12. Which statement is true concerning the charging of a wet cell nickel-cadmium battery?

• (A) The specific gravity of the electrolyte will be generally unaffected by the state of charge. o (B) Extended trickle charging should be avoided. o (C) Add distilled water just prior to charging to insure proper mixing. o (D) The charging rate should never allow gassing.


13. What is a hydrometer used to measure?

• (A) specific gravity of a battery electrolyte o (B) amount of potable water a vessel is taking on o (C) power developed by a salt water service pump o (D) water pressure in a deck pipeline


14. Which characteristic or condition will have the greatest effect on increasing a hydraulic oil's viscosity?

• (A) Pressure o (B) Pour point o (C) Cloud point o (D) Vacuum



8/31/2017

U.S.C.G. Merchant Marine Exam QMED Q802 Electrician Illustrations: 9 15. An open in the armature of a DC motor is suspected, but is not found by visual inspection of the

commutator. What would be the next step in troubleshooting this problem?

o (A) conduct an insulation resistance test of the armature o (B) visually inspect the armature windings o (C) test the commutator for a ground • (D) conduct a bar to bar test of the armature


16. Which of the listed tools should be used to remove a tapered roller bearing from a shaft?

o (A) An acetylene torch and hammer o (B) A tapered "come-a-long" o (C) A steel drift pin and hammer • (D) An arbor press


17. What is the recommended method used to resurface an eccentric DC motor commutator?

o (A) burnish it with commutator stones o (B) use a hard canvas wiper o (C) use a hand stone • (D) turn it down in the ship's lathe


18. Where is the power necessary to energize the howler "relay" coil at the engine room station as shown in the illustration? Illustration EL-0093

• (A) comes from each station's hand-cranked generator o (B) is supplied from a battery or ship's power o (C) comes from pushing a button on the handset o (D) is conducted through the relay's contacts


19. Which of the electrical properties listed will always be the same across each component in a parallel circuit?

• (A) Voltage o (B) Resistance o (C) Impedance o (D) Current



8/31/2017

U.S.C.G. Merchant Marine Exam QMED Q802 Electrician Illustrations: 9 20. What would be the most probable cause for a high-pressure alarm to be activated in a low-pressure

CO2 fixed fire extinguishing system?

o (A) An excessive amount of insulation has been installed on the tank and piping. o (B) An air leak has developed in the tank. • (C) The tank cooling system has malfunctioned. o (D) The pilot cylinder discharge valve is leaking.


21. When an alternator is to remain idle for even a few days, what should be done?

o (A) lift the brushes and disconnect the pigtails o (B) open the equalizing bus disconnect switch o (C) insulate the collector rings with strips of cardboard • (D) energize the space heater circuit


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

o (A) high mica segments on the stator bus bar • (B) an open in the rotor field circuit o (C) short circuit in the stator coils o (D) a tripped bus circuit breaker


23. When charging, which of the following represents the recommended maximum allowable temperature for electrolyte in a lead-acid battery?

• (A) 110°F o (B) 145°F o (C) 165°F o (D) 212°F


24. As a firefighting medium, CO2 can be dangerous under certain conditions as it can cause __________.

o (A) hallucinations o (B) carbon monoxide poisoning o (C) undulation • (D) freeze burns and blistering



8/31/2017

U.S.C.G. Merchant Marine Exam QMED Q802 Electrician Illustrations: 9 25. In performing routine maintenance of a ship's service alternator, what should be included?

o (A) lubricating exciter slip rings o (B) megger testing of all rectifying diodes • (C) periodic cleaning of the air filters or screens o (D) changing the pedestal bearing insulation yearly


26. The characteristics of the device shown in figure "8" of the illustration includes a stable voltage and low current while operating. Because of this, it can be suitably used in what type of circuit? Illustration EL-0065

• (A) switching and timing circuits o (B) class A and B amplifiers o (C) DC power supplies o (D) SCR power circuits


27. Which of the following statements describes what will occur if the motor torque-speed and current-speed curves shown in the illustration is required to carry 150% of full load? Illustration EL-0056

o (A) The slip value, stator current curve, and torque curve will all coincide. o (B) The slip will decrease. o (C) The torque will decrease. • (D) The stator current will increase.


28. When welding or burning aboard a vessel, you must be certain that the space __________.

o (A) contains no explosive fumes o (B) has no oil or flammable material in the area o (C) is properly vented • (D) all of the above


29. What is a useful instrument for checking 3-phase AC motor performance by measuring possible unbalanced currents?

• (A) clamp-on ammeter o (B) vibrating-reed frequency meter o (C) D'Arsonval iron-vane probe o (D) hand or battery-operated megger



8/31/2017

U.S.C.G. Merchant Marine Exam QMED Q802 Electrician Illustrations: 9 30. Which of the following statements represents an application of a silicon controlled rectifier?

o (A) Used in photocell sensor circuits for boiler burners. • (B) Provides DC power for a main propulsion motor. o (C) Used as a voltage reference diode. o (D) Used to eliminate AC power supply hum.


31. In DC motor construction, where are the commutating windings wound?

o (A) opposite main poles • (B) interpoles o (C) adjacent main poles o (D) the rotor core


32. In a forced-feed lubrication system, what statement is true concerning lube oil reservoir/sump residence time?

o (A) The lower the oil level, the longer the residence time, and the cooler the oil will be as delivered by the pump.

• (B) The lower the oil level, the shorter the residence time, and the hotter the oil will be as delivered by the pump.

o (C) The lower the oil level, the longer the residence time, and the hotter the oil will be as delivered by the pump.

o (D) The lower the oil level, the shorter the residence time, and the cooler the oil will be as delivered by the pump.


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

o (A) resistance meter • (B) voltmeter o (C) megohmmeter o (D) continuity tester


34. Which figure represents the schematic symbol shown in figure "2"? Illustration EL-0034

o (A) figure "A" • (B) figure "B" o (C) figure "C" o (D) figure "D"



8/31/2017

U.S.C.G. Merchant Marine Exam QMED Q802 Electrician Illustrations: 9 35. What is the instrument called a galvanometer used to measure?

o (A) thickness of galvanized metal o (B) resistance of electrical wiring insulation o (C) quantity of galvans in an electric circuit • (D) very small amounts of current


36. 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-contact voltage tester • (B) an auto ranging digital multimeter o (C) a solenoid type voltage tester o (D) a non-auto ranging digital multimeter


37. The individual 6 volt lead-acid batteries, when connected as shown in the illustration, as a battery bank would produce how many volts? Illustration EL-0070

• (A) 6 o (B) 12 o (C) 18 o (D) 24


38. The safe and efficient use of the face piece of a self-contained breathing apparatus is directly influenced by __________.

o (A) the stowing of the face piece o (B) the donning of the face piece o (C) the maintenance of the face piece • (D) all of the above


39. A hand portable CO2 fire extinguisher is effective on burning oil only __________.

o (A) if applied in connection with foam • (B) if applied promptly o (C) to prevent rekindling o (D) if attempts to extinguish the fire with low velocity fog have failed



8/31/2017

U.S.C.G. Merchant Marine Exam QMED Q802 Electrician Illustrations: 9 40. Before measuring an unknown resistance with an analog multimeter set up as an ohmmeter, what

should you do?

o (A) change the meter's batteries o (B) adjust the meter's pointer to mid-scale o (C) center the meter's pointer at infinity • (D) short the test leads and calibrate the meter reading to 'zero'


41. At a minimum threshold, how many milliamps of current through the body produces a condition where most people would suffer ventricular fibrillation and could only be resuscitated with a ventricular defibrillator?

o (A) 3 to 7 mA o (B) 10 to 16 mA o (C) 30 mA • (D) 75 mA for 5 sec.


42. In testing a three-phase delta-connected winding for an open circuit using a ohmmeter, what must be done?

o (A) measure the voltage across the open connections while testing o (B) test the windings as parallel groups to avoid short circuiting • (C) if possible, open the delta-connections to avoid shunting the phase being tested o (D) test each phase with all connections intact


43. A gate valve installed in a piping system should be used __________.

o (A) to throttle the flow of liquid o (B) only for lube oil service o (C) only with the stem facing down • (D) in either fully closed or fully opened positions


44. 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?

o (A) double o (B) remain the same • (C) be divided by two o (D) be divided by four



8/31/2017

U.S.C.G. Merchant Marine Exam QMED Q802 Electrician Illustrations: 9 45. When treating a person for third degree burns, you should __________.

o (A) make the person stand up and walk to increase circulation o (B) break blisters and remove dead tissue o (C) submerge the burn area in cold water • (D) cover the burns with thick sterile dressing


46. In comparing a semiconductor diode to a vacuum tube diode, what statement is true?

o (A) The semiconductor diode has longer life, no warm-up time, and is more delicate than the vacuum tube diode.

o (B) The semiconductor diode has shorter life, no warm-up time, and is less delicate than the vacuum tube diode.

o (C) The semiconductor diode has longer life, longer warm-up time and is less delicate than the vacuum tube diode.

• (D) The semiconductor diode has longer life, no warm-up time, and is less delicate than the vacuum tube diode.


47. A loud buzzing noise coming from the contacts in a magnetic controller can be caused by what condition?

o (A) excessive current o (B) bouncing of contacts o (C) excessive magnet gap • (D) dirt on magnet faces


48. For any given volume of compressed air produced by a multi-stage air compressor, interstage cooling will __________.

• (A) decrease the power required for compression o (B) allow the compressed air volume to remain constant o (C) allow isothermal compression of the air charge o (D) increase the power required for compression



8/31/2017

U.S.C.G. Merchant Marine Exam QMED Q802 Electrician Illustrations: 9 49. AC circuits can possess characteristics of resistance, inductance, and capacitance. In terms of units

of measure, how is the capacitive reactance of the circuit expressed?

o (A) mhos o (B) henrys • (C) ohms o (D) farads


50. The clamp-on AC ammeter consists essentially of a split-core and a rectifier-type instrument connected to the secondary winding of a particular type of transformer. Which type is used?

o (A) control transformer o (B) reactance transformer o (C) potential transformer • (D) current transformer


51. How does a circuit breaker differ from a fuse?

o (A) a circuit breaker melts and must be replaced, a fuse does neither o (B) a circuit breaker gives no visual indication of having opened the circuit, a fuse universally

does o (C) a circuit breaker is enclosed in a tube of insulating material with metal ferrules at each end, a

fuse is not • (D) a circuit breaker trips to break the circuit and may be reset, a fuse may not be reset


52. When would be the safest time to close the ship's main switchboard "shore power" circuit breaker?

o (A) at any time in a shipyard • (B) when the ship's generators have been disconnected from the main bus o (C) only after the ship's generators have been directly paralleled to those on shore o (D) if a quick disconnect coupling is used


53. Which of the listed instruments can be best used to locate a grounded field coil in a synchronous motor onboard ship?

• (A) Megohmmeter o (B) Voltmeter o (C) Frequency meter o (D) Multimeter



8/31/2017

U.S.C.G. Merchant Marine Exam QMED Q802 Electrician Illustrations: 9 54. The electrical diagram shown in figure "B" of the illustration represents what type of DC motor?

Illustration EL-0054

o (A) shunt-wound DC motor o (B) permanent magnet DC motor • (C) compound-wound DC motor o (D) series-wound DC motor


55. There is always a lower water pressure at the fire hose outlet than is found at the discharge of the pump. Which of the following reasons is the common cause of this loss in pressure?

• (A) Friction in the piping and valves o (B) Leaky pump suction valve o (C) Wear in the hydrant o (D) Leaky pilot valve


56. Which of the following procedures reduces the possibility of an interior ventilation duct fire from rapidly spreading?

o (A) Keeping the duct exterior clean. o (B) Having a portable CO2 ready at each duct opening. o (C) Having a fire hose charged at each duct opening. • (D) Keeping the duct interior clean.


57. What type of rotor is used in the split-phase family of single-phase motors?

o (A) Salient pole o (B) Drum o (C) Wound-rotor • (D) Squirrel-cage


58. Which of the following is NOT a treatment for traumatic shock?

o (A) Have the injured person lie down. o (B) Keep the patient warm, but not hot. o (C) Relieve the pain of the injury. • (D) Massage the arms and legs to restore circulation.



8/31/2017

U.S.C.G. Merchant Marine Exam QMED Q802 Electrician Illustrations: 9 59. The best type of chisel to use for cutting a keyway is the __________.

o (A) round nose chisel • (B) cape chisel o (C) flat cold chisel o (D) diamond point chisel


60. What is the name of the force that causes free electrons to flow in a conductor producing electric current?

• (A) electromotive force o (B) dielectric force o (C) inductive force o (D) resistant force


61. When performing routine AC motor maintenance what should be included?

o (A) inspection of the motor's internals for loose rotor bars or field poles o (B) verifying RPM if a synchronous motor • (C) temperature readings at normal loads to detect abnormal temperature rises o (D) rotor balance check


62. What is the functional name of an electrical device which prevents simultaneous energization of loads thereby preventing damage or injury?

• (A) electrical interlock device o (B) monitoring device o (C) modulating device o (D) mechanical limit device


63. What would be the effect of carrying field excitation excessively high on a synchronous motor?

o (A) a tendency for the motor to overspeed • (B) a tendency for the motor to overheat o (C) a loss of motor speed regulation o (D) a tendency for the motor to fall out of step



8/31/2017

U.S.C.G. Merchant Marine Exam QMED Q802 Electrician Illustrations: 9 64. A centrifugal bilge pump requires priming __________.

o (A) to initially unload the pump by having its head pressure equal to discharge pressure o (B) in order to overcome the potential energy of water in the discharge line o (C) primarily to lubricate the shaft seals • (D) due to the inability of this type of pump to lift water to cover the suction (eye) of the impeller


65. When testing the rotor of a synchronous motor for short circuits, a low voltage source is applied across the rotor coils through the collector rings. What would be the indication of a short-circuited coil?

o (A) high voltage drop reading, while the other coil readings will have an equal or lower value • (B) low or zero voltage drop reading, while the other coils will have higher readings o (C) steady voltmeter reading, while the other coil readings are fluctuating o (D) fluctuating voltmeter reading, while the other coil readings are steady


66. What could cause a very slow, but continual loss of electrolyte level from the cells of a storage battery?

o (A) one or more filler caps installed too tightly o (B) the specific gravity being higher than normal o (C) too low a charging rate • (D) evaporation of the water


67. What is true concerning all of the connecting conductors of a DC series circuit?

o (A) they all have the same power expended in them o (B) they all have the same resistance to current flow o (C) they all have the same voltage drop across them • (D) they all have the same current passing through them


68. As shown in figure "A" of the illustration if the applied voltage is 12 VDC, the resistance of R1 is 10 ohms, and R2 is 10 ohms, what is the current flowing through R1 when the switch is closed? Illustration EL-0020

• (A) 0.6 amp o (B) 0.833 amp o (C) 1.2 amps o (D) 2.4 amps



8/31/2017

U.S.C.G. Merchant Marine Exam QMED Q802 Electrician Illustrations: 9 69. In the system shown in the illustration, the engine room station is unable to signal any other station,

nor is any other station able to signal the engine room station. The engine room station can, however, ring itself by proper positioning of its selector switch. What is the most probable cause of this problem? Illustration EL-0093

o (A) The coil of component "C" of the problem station is open-circuited. o (B) The selector switch is grounded at the problem station diverting current from the other

stations' ringing devices. o (C) The switch at component "A" of the problem station is stuck open. • (D) There is an open between terminal "C" of the problem station and the common wire of the

multi-conductor cable to the other stations.


70. 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?

• (A) 3 to 7 mA o (B) 10 to 16 mA o (C) 30 mA o (D) 100 mA for 2.5 sec.



8/31/2017


6/1/2016

EL-0020

Adapted for testing purposes only Further reproduction prohibited without permission.



6/1/2016

EL-0034




6/2/2016

EL-0054




3/30/2015

Adapted for testing purposes only from HUBERT, Operating, Testing and Preventive Maintenance

of Electrical Power Apparatus. © 2003 Pearson Education. Reproduced with permission

from Pearson Education, Inc. Further reproduction prohibited without permission.

EL-0056



6/2/2016

EL-0065




6/2/2016

EL-0070




6/2/2016

EL-0088




6/2/2016

EL-0093




6/2/2016

EL-0148

Adapted for testing purposes only from HUBERT, Operating, Testing, and Preventive Maintenance of Electrical Power Apparatus

Copyright © 2003 by Pearson Education

Reproduced with permission from Pearson Education, Inc. Further reproduction prohibited without permission.

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Q802 Electrician

u.s.c.g. merchant marine exam qmed q802 … · duration of contact), contact with an energized...

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