更多"A switchboard, for a AC electrical "的相关试题:
[单项选择]A switchboard for an AC electrical system requires the use of which of the following devices（）.
A. Frequency meter
B. Ohmmeter
C. Induction voltage regulator
D. Current transformer governor
[单项选择]The purpose of a main switchboard circuit breakers reverse-power trip is to （）.
A. prevent main circuit overload
B. protect the circuit breaker blowout coil
C. prevent alternator motorization
D. prevent low voltage tripout
[单项选择]An alternator switchboard has a synchroscope and synchronizing lamps, if the synchroscope is broken, which of the steps listed is the most essential before an alternator can be paralleled with the bus （）
A. The breaker should be closed when one synchronizing lamp is dark and the other is bright
B. The breaker should be closed when both synchronizing lamps are bright
C. The frequency meter should be used to determine that the incoming alternator frequency is slightly higher than the bus
D. A portable phase sequence indicator must be used to verify the information from the lamps
[单项选择]（）are supplied by main switchboard directly.
A. Suez Canal searchlight, air compressor and air conditioning compressor
B. Air compressor, boiler blower and refrigeration plant
C. Boiler blower, Suez Canal searchlight and refrigeration plant
D. Suez canal searchlight, air compressor and boiler blower
[单项选择]An indicator on the main switchboard should show （） the emergency battery is in service or not.
A. that
B. when
C. if
D. whether
[单项选择]（）is power supplied by main switchboard directly not through sub-board.
A. Deck machinery
B. Little power load
C. Some important load
D. stationary submersible pump
[单项选择]（）is not installed on the main switchboard.
A. Ammeter and changeover switch
B. Power factor meter
C. Synchroscope
D. Reverse sequence relay
[单项选择]（）is not installed on the emergency switchboard.
A. Control panel
B. Paralleling panel
C. Load panel
D. Busbar
[单项选择]To （） , the power is supplied by main switchboard directly not though sub-board.
A. save network cost
B. improve the reliability of supplying power to important load
C. prevent sequence reverse
D. increase the power factor of important load
[单项选择]（）is not a part of the main switchboard.
A. Busbar
B. Load panel of main generator
C. Paralleling panel
D. Shore connection box
[单项选择]A “dead front” switchboard is one （）.
A. without switches on it
B. with insulated switches and no exposed terminals
C. without circuit breakers
D. without safety hand nails nor rubber mats
[单项选择]（） is (are) not power supplied by main switchboard directly.
A. Steering gear and windlass
B. Navigation light and radio power panel
C. Navigation device power box
D. Daily fresh water pump
[名词解释]土壤空间分布 soil spatial distribution
[单项选择]Electrical circuits are protected against overheating by means of a/an （）.
A. circuit breaker
B. amplifier
C. diode
D. capacitor
[判断题]石油密度计分为SY-I型和SY-II型两种型号。
[单项选择]Making cargo plan for appropritate distribution of the cargo on board is（）duty.
A. a ship's officer's
B. a tallyman's
C. a port planner's
D. a foreman's
[单项选择]Making cargo plan for appropriate distribution of the cargo on board is（）duty．
A. a ship's officer's
B. a Tallyman's
C. a port planner's
D. a foreman's
