网友您好， 请在下方输入框内输入要搜索的题目：
题目内容
（请给出正确答案）
（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
参考答案
更多 “（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
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.
考题
The frequency of an AC generator is controlled by the ___.A.rheostatB.governorC.exciterD.capacitor
考题
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
考题
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
考题
单选题The purpose of DC generator brushes is to （）.A
neutralize armature reactionB
conduct electric current to an outside circuitC
convert DC current to AC currentD
provide excitation to a DC generator
考题
单选题The overcurrent relay （） the motor contactor when the motor exceeds its rated current.A
connectsB
tripsC
foulsD
destructs
考题
单选题A DC generator is used to supply direct current in order to maintain an AC generator field and is known as a/an （）A
rotorB
statorC
exciterD
armature
考题
单选题When securing an AC generator, you should FIRST （）.A
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
单选题The frequency of an AC generator is controlled by the （）A
rheostatB
governorC
exciterD
capacitor
考题
单选题An emergency diesel generator should automatically shut down in the event of （）A
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Which of the following statements represents the main difference between a relay and a contactor?（）A
Contactors control current and relays control voltageB
A relay is series connected and a contactor is parallel connectedC
Contactors can handle heavier loads than relaysD
Contactors are made from silver and relays are made from copper
考题
单选题（）of the following need not be entered in the official logbook?A
The testing of the internal combustion engine driven emergency generator at least once each month the vessel is navigatedB
The testing of storage betteries for emergency lighting and systems once each 6 months the vessels is navigatedC
The actual draft when the vessel arrives in salt water after department a portD
The testing of the line-throwing appliance once every 3 months
考题
单选题A diesel generator has just been paralleled with an AC turbo-generator, but the load can not be properly divided.This could be caused by（）A
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
单选题The initial voltage of self-excitation generator set up by（）A
residual magnetismB
voltage regulatorC
electrical current for excitationD
the other running generator
考题
单选题Which of the following should be the FIRST step in removing a generator from parallel operation?（）A
Trip the generator off the switchboardB
Turn off all electrical equipmentC
Remove the load from the off going generatorD
Increase the cycles of the generator staying on the line
考题
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
考题
单选题When paralleling two AC generators, the frequency of the machine coming on-line, immediately prior to closing its breaker, should be （）A
slightly less than the oncoming generator frequencyB
the same as the bus frequencyC
slightly greater than the bus frequencyD
the same as the bus voltage
热门标签
最新试卷