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Brushless generators are designed to operate without the use of_____.
A.brushes
B.slip rings
C.commutators
D.all of the above
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Which command （without options） would you use to display how much space is available on all mounted partitions？（）
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单选题Which of the following statements is true concerning all three-phase alternators?（）A
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Each has one armature winding acted on by three identical but separate systems of rotating magnetsC
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单选题Which is a function of the voltage regulators used with AC generators?（）A
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单选题When the prime movers of two paralleled generators are equipped with mechanical- hydraulic governors, and are operating within their designed range, the unit with the least amount of speed droop will （）.A
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Circulating currents are kept to a minimumB
Field excitation losses are kept to a minimumC
Generator rotors will have a lesser tendency to huntD
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brushesB
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单选题A fixed carbon dioxide extinguishing system for a machinery space，designed WITHOUT a stop valve in the line leading to the protected space，is actuated by（）.A
one controlB
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none of the above
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pulseB
exhaustC
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单选题What is TRUE of pressure/vacuum valves? （）A
They are designed to provide for the flow of small volumes of tank atmospheres caused by thermal variations in a cargo tankB
They should operate in advance of the pressure/vacuum breakersC
They should be kept in good working order by regular inspection and cleaningD
All of the above
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