A.are less expensive
B.require less maintenance
C.can be started across the line
D.offer a more effective means of controlling speed
您可能感興趣的試卷
你可能感興趣的試題
A.Alternators
B.Wave guides
C.Exciters
D.Amplidynes
A.quartered
B.unchanged
C.doubled
D.quadrupled
A.both generate alternating voltages
B.both rectify the voltage before delivery
C.are constructed at the same physical size for the same kilowatt rating
D.both supply three-phase power
A.increase the field excitation
B.decrease the field excitation
C.increase the number of magnetic poles
D.increase the speed of the prime mover
A.in series with the power source and load
B.in parallel with the power source and load
C.insuring correct polarity
D.using the lowest range possible to prevent instrument damage
最新試題
The shipboard oil pollution emergency plan will be invalid after （）
The main purpose of port State control is not to（）
“Insufficiency of manning or insufficiency of certification of seafarers” is an identification of a（）
When does auxiliary burner of incinerator put into operation? （）Ⅰ. start incinerator when it is coldⅡ. the sludge for dealing with is littleⅢ. the sludge for dealing with is largeⅣ. the water and impurity in sludge are too muchⅤ. the temperature in incinerator is lowⅥ. dealing with little solid rubbish
Which one is NOT the ‘clear grounds’ for a more detailed inspection?（）
Using a file without a handle may result in （）
To proceed to the assistance of a ship in distress is（）
One of the reasons that cause oil flowed from sludge outlet of a self-cleaning separator is（）
The treatment of the fuel oils involves storage, heating, filtering and（）
If two A.C.generators are to be operated in parallel, the load is distributed evenly by（）