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单选题
In a modern three-phase A-Csynchronous brushless generator, the excitation winding is on the rotorThat means （）.
A
The generator needs not excitation
B
The winding on the rotor is for inputting excitation current
C
There are three phase windings on the rotor
D
The generator has brushes
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更多 “单选题In a modern three-phase A-Csynchronous brushless generator, the excitation winding is on the rotorThat means （）.A The generator needs not excitationB The winding on the rotor is for inputting excitation currentC There are three phase windings on the rotorD The generator has brushes” 相关考题
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In a modern three-phase A.C. synchronous brushes generator, the excitation winding is on the rotor. That means .A.The generator need not excitation.B.The winding on the rotor is for inputting excitation current.C.There are three phase windings on the rotor.D.The generator has no brushes.
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考题
单选题Which of the following statements is true concerning all three-phase alternators?（）A
Each has three separate but identical armature windings acted on by one system of rotating magnetsB
Each has one armature winding acted on by three identical but separate systems of rotating magnetsC
All three-phase alternators are designed to operate with a O8 leading power factorD
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考题
单选题The purpose of DC generator brushes is to （）.A
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conduct electric current to an outside circuitC
convert DC current to AC currentD
provide excitation to a DC generator
考题
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open the generator circuit breakerB
switch the voltage regulator to “manual”C
decrease the field excitation to minimumD
reduce the load on the unit
考题
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rheostatB
governorC
exciterD
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dangerous over-speedingB
a loss of lube oil pressureC
activation of the fixed CO2 system for the emergency generator spaceD
all of the above
考题
单选题In a three-phase circuit, the phase voltages are （）A
120°apartB
160°apartC
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单选题Adam Smith was a professor of philosophy, a commissioner of customs, and founded the field of modern economics.A
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考题
单选题Brushless generators are designed to operate without the use of（）.A
brushesB
slip ringsC
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考题
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an incorrect diesel generator governor speed droop adjustmentB
a faulty reverse power relay within the main circuit breaker assemblyC
unsynchronized isochronous load distribution adjustmentsD
a different speed setting on each unit
考题
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residual magnetismB
voltage regulatorC
electrical current for excitationD
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power factor meterC
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60B
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考题
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Turn off all electrical equipmentC
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考题
单选题AC and DC generators are similar in that they （）A
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考题
单选题The DC excitation to the field of brushless synchronous is generally produced by （）A
an exciter driven by the same shaft with the generatorB
an exciter driven by external prime moverC
generator itselfD
either A and B
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