（EMB145）Generator Line Contactor闭合的条件是（）A、只有发电机的电压B、发电机电压和速度C、只有发电机的速度
（EMB145）Generator Line Contactor闭合的条件是（）
- A、只有发电机的电压
- B、发电机电压和速度
- C、只有发电机的速度
相关考题：
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.
The frequency of an AC generator is controlled by the ___.A.rheostatB.governorC.exciterD.capacitor
ConErr165（DCbus undervoltage at Line Contactor closed）加载到网侧变频器，直流母排电压不能到达1050VDC，一般为（）问题，直接更换。A、网侧变频器；B、机侧变频器；C、发电机；D、Crowbar
当电子舱出现烟雾时，按压应急电源控制面板上的“GEN1LINE”按钮后，下列说法正确的是A、闭合GLC1(GEN LINE CONTACTOR),左右＃1燃油泵由AC BUS 1直接供电断开B、断开GLC1(GEN LINE CONTACTOR),左右＃1燃油泵由IDG#1直接供电C、闭合BTC1(BUS TIE CONTACTOR),左右＃1燃油泵由AC BUS 1直接供电断开
单选题The purpose of DC generator brushes is to （）.Aneutralize armature reactionBconduct electric current to an outside circuitCconvert DC current to AC currentDprovide excitation to a DC generator
单选题The overcurrent relay （） the motor contactor when the motor exceeds its rated current.AconnectsBtripsCfoulsDdestructs
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单选题Which of the following statements represents the main difference between a relay and a contactor?（）AContactors control current and relays control voltageBA relay is series connected and a contactor is parallel connectedCContactors can handle heavier loads than relaysDContactors are made from silver and relays are made from copper
单选题（）of the following need not be entered in the official logbook?AThe testing of the internal combustion engine driven emergency generator at least once each month the vessel is navigatedBThe testing of storage betteries for emergency lighting and systems once each 6 months the vessels is navigatedCThe actual draft when the vessel arrives in salt water after department a portDThe testing of the line-throwing appliance once every 3 months
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单选题The initial voltage of self-excitation generator set up by（）Aresidual magnetismBvoltage regulatorCelectrical current for excitationDthe other running generator
单选题Which of the following should be the FIRST step in removing a generator from parallel operation?（）ATrip the generator off the switchboardBTurn off all electrical equipmentCRemove the load from the off going generatorDIncrease the cycles of the generator staying on the line
单选题In a modern three-phase A-Csynchronous brushless generator, the excitation winding is on the rotorThat means （）.AThe generator needs not excitationBThe winding on the rotor is for inputting excitation currentCThere are three phase windings on the rotorDThe generator has brushes
单选题When paralleling two AC generators, the frequency of the machine coming on-line, immediately prior to closing its breaker, should be （）Aslightly less than the oncoming generator frequencyBthe same as the bus frequencyCslightly greater than the bus frequencyDthe same as the bus voltage