更多"A ground in an electrical circuit o"的相关试题:
[单项选择]A ground can be defined as an electrical connection between the wiring of a motor and its（）.
A. shunt field
B. circuit breaker
C. metal framework
D. inter-pole
[单项选择]An auxiliary reservoir for starting auxiliary engines should be kept at （）.
A. low pressure at all times
B. full pressure at all times
C. low pressure at intermittence
D. full pressure at intermittence
[单项选择]Fuel oil contamination of an auxiliary diesel engine lube oil can result in（）
A. an increased flash point
B. higher lube oil pressures
C. an increased viscosity
D. lower lube oil pressures
[单项选择]When the normal compression ratio of a diesel engine is not very high, misfiring at light loads may be caused by （）
A. overloading the engine
B. low exhaust valve lift
C. excessive cylinder cooling
D. insufficient mechanical clearance
[单项选择]What harmful condition can result if a diesel engine is operated at very light loads for long periods of time?（）
A. increased carbon buildup
B. burning of intake valves
C. excessive firing pressures
D. increased fuel consumption
[单项选择]If a single cylinder relief valve on a diesel engine lists frequently while the engine is running, the cause may be an （）
A. excessively late injection timing for each cylinder
B. incorrectly adjusted intake valve timing
C. incorrectly adjusted fuel injector
D. incorrectly adjusted intake valve clearance
[单项选择]About the jacket water, that of the auxiliary engines usually（） is circulated by pumps, and the main engine usually （）
A. an engine-driven；as well
B. an engine-driven；has an independent pump
C. an independent；as well
D. an independent；has an engine-driven pump
[单项选择]Most large, low-speed, main propulsion diesel engines use duplex lube oil strainer to （）
A. decrease the time required between cleanings
B. removes all large and small foreign objects
C. ensure a positive flow of oil at all times
D. ensure that all lube oil has been treated twice
[单项选择]When an air started, four-stroke/cycle diesel engine is being cranked, the starting air is admitted to each cylinder during what would normally be the（）
A. intake stroke
B. compression stroke
C. power stroke
D. exhaust stroke
[单项选择]The breaking-up of fuel as it enters a diesel engine cylinder is known as（）
A. airification
B. vaporization
C. atomization
D. gasification
[单项选择]The intake ports of a two-strike/cycle diesel engine are opened and closed by the action of the （）
A. camshaft
B. piston movement
C. exhaust valves
D. vertical drive
[单项选择]Diesel oil may be used to cool （） of a diesel engine.
A. cylinders
B. exhaust valves
C. pistons
D. fuel valves
[名词解释]SELV回路（SELV circuit）
[单项选择]Electrical circuits are protected against overheating by means of a/an （）.
A. circuit breaker
B. amplifier
C. diode
D. capacitor
[名词解释]电气设备（electrical equipment）
[单项选择]Accidental grounds in a shipboard electrical system must be repaired as soon as possible as they will （）
A. result in immediate power outages
B. damage circuit breakers
C. appear on the ground detection system
D. damage insulation and may cause outages
[单项选择]Electrical power is expressed in （）
A. ohms
B. volts
C. amps
D. watts
[单项选择]The greatest detrimental effect on idle electrical equipment, such as cargo pump motors, is the（）.
A. loss of residual magnetism
B. absorption of moisture in the insulation
C. insulation varnish flaking
D. dirt collecting on the windings
[单项选择]Grease coatings on electrical contact surfaces increase contact resistance and should be removed with a/an （）.
A. small wire brush
B. compressed air jet
C. clean dry cloth
D. 10% solution carbon solvent and water
