Which of the listed precautions should be observed before spraying liquid solvent on the insulation of an electric motor? A. Slow the motor down to low speed. B. Disconnect the motor from the power source. C. Secure all ventilation in the area. D. Preheat the insulation to assist in cleaning.

Which of the listed precautions should be observed before spraying liquid solvent on the insulation of an electric motor? A. Slow the motor down to low speed. B. Disconnect the motor from the power source. C. Secure all ventilation in the area. D. Preheat the insulation to assist in cleaning.
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Answer: B
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Which of the listed precautions should be taken when cleaning the internals of a motor with compressed air? A. Open the machine on both ends so as to allow the air and dust to escape. B. Be certain that the circuit breaker is opened and tagged on the feeder panel. C. Be certain that the air is clean and as dry as possible. D. All of the above.

Description : Which of the listed precautions should be taken when cleaning the internals of a motor with compressed air? A. Open the machine on both ends so as to allow the air and dust to escape. B. Be certain that the ... panel. C. Be certain that the air is clean and as dry as possible. D. All of the above.

Last Answer : Answer: D

Which of the following procedures should be used to maintain a large electric motor during periods of inactivity? A. A thin layer of air-drying varnish should be applied on the windings. B. Compressed air should be blown over areas where dust is deposited. C. Spraying a solvent periodically to remove carbon dust. D. Space heaters should be used to prevent condensation of moisture.

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Last Answer : Answer: D

Which of the conditions listed will indicate the need to clean the insulation on the windings of an electric motor? A. Higher than normal operating temperature. B. Excessive vibration at normal speed. C. Sparking at the brushes. D. High megger readings.

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Routine maintenance of dry-type transformers should include ____________. A. cleaning the windings, if accessible, with a vacuum cleaner or very low pressure air B. measuring and recording the winding temperature with an accurate mercury thermometer C. periodic cleaning of the winding insulation with an approved solvent D. making sure that the units are close to bulkheads or corners to protect them from damage

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Last Answer : Answer: A

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Last Answer : Answer: C

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To repair a small electrical motor that has been submerged in saltwater, you should _____________. A. wash it with fresh water and apply an external source of heat B. renew the windings C. send it ashore to an approved service facility D. rinse all electrical parts with a carbon tetrachloride cleaning solvent and then blow dry the motor with compressed air

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Last Answer : Answer: A

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Last Answer : Answer: D

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Last Answer : Answer: B

The insulation resistance of a DC motor is observed to be 15 MΩ at a temp. of 70°C. what is its value corrected to 40°C. the correction factor for 70°C is 8.0.

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Last Answer : Answer: B

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Last Answer : Answer: A

As load is added to a shunt motor, the motor will _________. A. speed up B. continue to operate at the same speed C. slow down slightly D. stop

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Last Answer : Answer: C

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Last Answer : Answer: A

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Which two components, shown in the illustration, acting together will disconnect the motor from the line in case of a sustained motor overload? EL-0080 A. 'G' and 'H' B. 'E' and 'I' C. 'F' and 'H' D. 'E' and 'G'

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If a small electric motor has been submerged in saltwater for a short period of time, you should _____________. A. send it ashore for rewinding B. rinse it with warm freshwater and bake it dry in an oven C. soak it in a bucket of commercial solvent and bake with internal heat D. clean it with carbon tetrachloride and blow it out with compressed air

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Last Answer : Answer: B

A delayed-action fuse is most frequently used in which of the listed circuits? A. Lighting circuit B. Motor circuit C. Electric heater circuit D. Radar circuit

Description : A delayed-action fuse is most frequently used in which of the listed circuits? A. Lighting circuit B. Motor circuit C. Electric heater circuit D. Radar circuit

Last Answer : Answer: B

Which of the instruments listed is used to check insulation resistance? A. Magneto B. Megohmmeter C. Dynamometer D. Rheostat

Description : Which of the instruments listed is used to check insulation resistance? A. Magneto B. Megohmmeter C. Dynamometer D. Rheostat

Last Answer : Answer: B

Which of the listed groups of electrical insulation materials is best suited for the highest operating temperatures? A. impregnated cotton and silk B. unimpregnated paper and cotton C. pure glass and quartz D. mica and porcelain with bonding agents

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Last Answer : Answer: D

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Description : Which of the listed statements is correct when using an analog multimeter as an ohmmeter? A. The pointer should be adjusted to zero each time a new resistance range is selected. B. The ... C. Ohmmeters are not sufficiently sized to measure conductor insulation resistance. D. All of the above.

Last Answer : Answer: D

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Last Answer : c) Wipe clean, using a clean cloth soaked in a solvent remover

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Last Answer : Answer: C

The insulation resistance of electric equipment and machinery should be tested for the lowest normal insulation values _____________. A. immediately after shutting down the machine B. every time the brush rigging is adjusted C. immediately after starting up the machine D. every 30 days whether the machine is in use or not

Description : The insulation resistance of electric equipment and machinery should be tested for the lowest normal insulation values _____________. A. immediately after shutting down the machine B. every time the brush rigging is ... starting up the machine D. every 30 days whether the machine is in use or not

Last Answer : Answer: A

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Description : An increase in which of the listed conditions will increase the speed of a synchronous motor? A. Frequency B. Voltage C. Armature current D. Inductance

Last Answer : Answer: A

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Description : Which of the following statements is true concerning the cleaning of electrical contacts? A. Compressed air should be used to blow out metallic dust. B. Magnetic brushes should be used to remove ... contact resistance. D. Delicate parts should be cleaned with a brush and an approved safety solvent.

Last Answer : Answer: D

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If deck machinery is expected to be idle for an extended period of time you should____________. A. have electrical safety gloves available in case of electrical shock before running B. perform a 'high pot' test to determine the condition of the insulation C. water wash the motor and controller to remove any salt that may interfere with smooth operation D. check run at regular intervals to inusre correct operation and to renew the internal coating of lubrication

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Last Answer : Answer: D

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Discuss how the ventilation and cooling of large high speed alternator is carried out.

Description : Discuss how the ventilation and cooling of large high speed alternator is carried out.

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In order to safely carry out repairs to a generator circuit breaker, it must be isolated from the bus. This is accomplished by opening the _____________. A. reverse power relay B. bus disconnect link C. generator bus fuse connections D. power directional relay

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Last Answer : Answer: B

A shore power circuit breaker should be closed only _____________. A. when the ship's generators have been directly paralleled to those on shore B. in a shipyard C. if a quick disconnect coupling is used D. when the ship's generators have been removed from the bus

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Last Answer : Answer: D

In an emergency, the fastest way to interrupt power and stop the winch shown in the illustration is for the ____________. EL-0102 A. mate to open the disconnect switch at 'L1' and 'L2' B. winch operator to open the 'safe switch' at the 'master switch' C. engine room watch engineer to open the winch circuit breaker D. electrician to open the test link at the controller

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Last Answer : Answer: B

The part of the shipboard electrical system used to control the distribution of power to the branch circuits, is the _____________. A. bridge control panel B. disconnect links C. governor relay box D. main switchboard

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Last Answer : Answer: D