更多"Complete maintenance of electrical "的相关试题:
[单项选择]The operator of electrical motors should keep a constant check on the loads they carry because （）
A. low loads necessitate frequent insulation cleaning
B. exceeding nameplate values shortens useful life
C. energy is wasted if full loading is not utilized
D. power factor correction methods are load dependent
[单项选择]Before doing maintenance on electrical equipment, you should （）.
A. turn off power first
B. turn on power first
C. with a test pen in hand
D. tell C/E
[单项选择]If you must jump from a ship，your posture should include（）.
A. holding down the life preserver against the chest with one arm crossing the other，covering the mouth and nose with a hand，and feet together
B. knees bent and held close to the body with both arms around legs
C. body straight and arms held tightly at the sides for feet first entry into the water
D. both hands holding the life preserver below the chin，with knees bent，and legs crossed
[单项选择]Which publication should you check for complete information on Puget Sound weather conditions? （）
A. Sailing Directions
B. Light List
C. Coast Pilot
D. Chart of the area
[单项选择]Which of the motors for the devices listed below is fitted with an instantaneous overload relay?（）
A. Fan
B. Pump
C. Winch
D. Machine tool
[单项选择]An advantage of DC motors over AC motors is that they （）
A. are less expensive
B. require less maintenance
C. can be started across the line
D. offer a more effective means of controlling speed
[单项选择]Which operation should be done when launching an inflatable liferaft by hand?（）
A. Open the liferaft casing
B. Turn the valve on the CO2 cylinder to start inflation
C. Make sure the operating cord is secured to the vessel before throwing it over the side
D. After inflation，detach operating cord from liferaft
[单项选择]On chart，bearings to near objects should be used in preference to objects farther off，because（）.
A. a small error in bearing or in laying it down on the chart has a greater effect in misplacing the position the longer the line to be drawn
B. all scales are kept updated for vital information by Notices to Mariners
C. the larger the scale of the chart，the greater the detail that can be shown on it
D. the mariner using the medium scale charts for passage along a coast need not transfer on to a large scale for short distances
[单项选择]Which of the valves listed should be used either in the fully opened or the fully closed position?（）
A. A gate valve
B. A globe valve
C. Any check valve
D. Any needle valve
[单项选择]I Should notice of acceptance of the Vessel’s classification records and of the Vessel not be received by the Sellers，the deposit together with interest earned shall be released immediately to the （），whereafter this Agreement shall be null and void.
A. Buyers
B. Sellers
C. either the Buyers or the Sellers
D. neither the Buyers no the Sellers
[单项选择]How should you signal the crane operator to stop in an emergency?（）.
A. Extend arm with the palm down and and hold this position rigidly
B. Place clasped hands in frontof your body
C. extend arm and move hand rapidly right and left with the plam outward
D. Place both fists in front of the body with the thumbs pointing outward
[单项选择]I should like to rent a house，modern，comfortable and（）in a quiet neighborhood.
A. all in all
B. after all
C. above all
D. over all
[单项选择]（）should not be considered as components as fire installations.
A. fire pumps
B. fire mains
C. hydrants and hoses
D. closing appliances which are kept permanently closed at sea
[单项选择]If （）,the PSCO should proceed to a more detailed inspection.
A. the PSCO’s general impression confirm a good standard of maintenance
B. the certificates are valid
C. the PSCO believes the ship doesn’t meet the requirements
D. the PSCO can’t find deficiencies at first glance
[单项选择]Diesel engine electric starting motors generally require heavier duty motors and motors and operate at higher voltages than comparable starting motors for gasoline engines due to（）
A. higher speed required
B. flywheel-effect
C. lower starting temperatures
D. higher compression pressures
[单项选择]Governors are equipped with motors for synchronizing, load sharing and frequency control（）
A. speed setting
B. load setting
C. speed changing
D. load changing
[单项选择]Starting motors，generators，and other spark producing devices should be mounted as high above the bilges as possible to（）.
A. keep them dry when the bilges are full of water
B. keep them cool when the vessel is underway
C. make them more accessible for repairs
D. prevent accidental ignition of any gasoline vapors that may have accumulated in the bilges
