If an attempt is made to hoist a load that exceeds the capacity of an electric winch，an overload safety device causes a circuit breaker to cut off the current to the winch motor ______．A.when the line pull reaches the rated winch capacityB.after the line pull exceeds the rated winch capacityC.after a short build-up of torqueD.immediately
If an attempt is made to hoist a load that exceeds the capacity of an electric winch，an overload safety device causes a circuit breaker to cut off the current to the winch motor ______．
A.when the line pull reaches the rated winch capacity
B.after the line pull exceeds the rated winch capacity
C.after a short build-up of torque
D.immediately
相关考题：
Electric insulation is made of organic substances and so gradually______with ageA.deterioratesB.increasesC.are fouledD.becomes better
To safeguard the operator and other personnel working on or near a hoisting operation, which of the following precautions should be observed?A.Keep a load on the hoist until all personnel are finished workingB.Set the load on a movable dolly when transportation may be neededC.Have one man keep a hand on the load to steady itD.Insure that the lifting gear capacity is not exceeded
Which device is designed to automatically hold the load if power should fail to an electric winch?A.Pneumatic brakeB.Electromagnetic brakeC.Hand brakeD.Motor controller
The load chart of a ship crane enables the operator to combine the load radius with boom length to determine the ______．A.Maximum counter weight requiredB.Minimum horsepower requiredC.Hoist rope strengthD.Allowable load
When a cargo boom or crane is rated at varying capacities，there will be a table at the controls which relates safe working load to ______．A.winch speedB.boom strengthC.load radiusD.cable strength
In vessel construction，a greater number of watertight bulkheads results in ______．A.increased capacity to set flooding boundariesB.decreased capacity to set flooding boundariesC.reduced compartmentationD.greater deck load capacity
If an electric cargo winch is being used to lift a draft of cargo and the engine room loses all power，which will occur ________．A.A pawl，forced by a spring mechanism，will engage the teeth of the bull gear and hold the loadB.An electromagnetic brake will hold the load where it is suspendedC.The load will fall rapidly to the deck unless the foot brake is engagedD.The load will slowly lower to the deck under control of the drag of the winch motor
When a winch breaks down，or some similar occurrence makes only one winch available at a hatch，which alternate rig would provide a temporary solution while repairs are made ________．A.Frisco RigB.Split fall rigC.West Coast RigD.Yard and stay jury rig
During startup, the router displays the following error message: boot: cannot open "flash:" What will the router do next?（）A、Because of damaged flash memory， the router will fail the POSTB、It will attempt to locate the IOS from a TFTP server. If this fails， it will initiate the setup dialog.C、It will attempt to locate the IOS from a TFTP server. If this fails， it will load a limited IOS from ROMD、It will attempt to locate the configuration file from a TFTP server. If this fails， it will initiate the setup dialog.E、It will attempt to locate the configuration file from a TFTP server. If this fails， it will load a limited configuration from ROM
During startup, the router displays the following error message: boot: cannot open "flash:" What will the router do next（）。A、Because of damaged flash memory, the router will fail the POST.B、It will attempt to locate the IOS from a TFTP server. If this fails, it will initiate the setup dialog.C、It will attempt to locate the IOS from a TFTP server. If this fails, it will load a limited IOS from ROM.D、It will attempt to locate the configuration file from a TFTP server. If this fails, it will initiate the setup dialog.E、It will attempt to locate the configuration file from a TFTP server. If this fails, it will load a limited configuration from ROM.
On traffic lanes where demand is strong and plane capacity is limited， the air rates will be （）and vice versa for traffic lanes where supply exceeds demand.A、lowB、highC、normalD、average
单选题In vessel construction，a greater number of watertight bulkheads results in（）.Aincreased capacity to set flooding boundariesBdecreased capacity to set flooding boundariesCreduced compartmentationDgreater deck load capacity
单选题During startup, the router displays the following error message: boot: cannot open "flash:" What will the router do next（）。ABecause of damaged flash memory, the router will fail the POST.BIt will attempt to locate the IOS from a TFTP server. If this fails, it will initiate the setup dialog.CIt will attempt to locate the IOS from a TFTP server. If this fails, it will load a limited IOS from ROM.DIt will attempt to locate the configuration file from a TFTP server. If this fails, it will initiate the setup dialog.EIt will attempt to locate the configuration file from a TFTP server. If this fails, it will load a limited configuration from ROM.
单选题杂货船可以用自己的吊杆装卸货物。（）AGeneral cargo ships may load and discharge by her own winch.BBulk carriers may handle cargo by her own derricks.CGeneral cargo ships may load and discharge by her own derricks.DGeneral cargo ships may load and discharge by cranes.
单选题Running an electric winch at slow speed over a long period of time causes（）.Athe speed to be retarded by the friction brakeBa load to go downward at full speedCthe circuit breaker to turn offDthe resistors to overheat and eventually burn out
单选题（） can be operated independently or locked together and operated as a twin-job cranes of double capacity.ATwo derricksBA derrick and a craneCTwo cranesDA crane and a winch
单选题When hoisting a boat on gravity type davits using an electric motor driven winch，the davit arms should be brought up（）.Ato their final position with the winch operating at slow speedBto the bar stop，and then hand cranked to their final positionCuntil just before they make contact with the limit switch，and then hand cranked to their final positionDto the embarkation deck，and then hand cranked to their final position
单选题Generators should have an excitation/voltage regulation system which will enable them to share the steady state reactive load （） no machine exceeds its proportional share of reactive load by more than 10% of the rated reactive load of the largest generator.AwhenBso asCsuch thatDthough
单选题If an attempt is made to hoist a load that exceeds the capacity of an electric winch，an overload safety device causes a circuit breaker to cut off the current to the winch motor（）.Awhen the line pull reaches the rated winch capacityBafter the line pull exceeds the rated winch capacityCafter a short build-up of torqueDimmediately
单选题The duty of a deck winch is to lift and lower a load by means of a fixed rope on （）.Aa warp endBa mooring winchCa worm gearDa barrel
单选题Electric cargo winches have an overload safety device which normally cuts the current to the winch motor（）.Aafter torque causes line pull to exceed the rated capacity of the winchBbefore the line pull reaches the rated capacity of the winchCwhen the line pull reaches the breaking strength of the fallDbefore the safe working load of the fall is reached
单选题To safeguard the operator and other personnel working on or near a hoisting operation which of the following precautions should be observed?（）AKeep a load on the hoist until all personnel are finished workingBSet the load on a movable dolly when transportation may be neededCHave one man keep a hand on the load to steady itDInsure that the lifting gear capacity is not exceeded
单选题Electric insulation is made of organic substances and so gradually （） with age.AdeterioratesBincreasesCare fouledDbecomes better
单选题If a hydraulic pump on a winch accidentally stops while hoisting，the load will stay suspended because（）.Aa check valve will close that prevents reverse circulationBa centrifugal counterweight counteracts the force of gravityCthe electric pump motor will cut outDthe control lever will move to the stop position
单选题The drowning boy made a _____ attempt to catch the rope thrown to him.AdangerousBgracefulCgentleDdesperate
单选题Which device is designed to automatically hold the load if power should fail to an electric winch?（）APneumatic brakeBElectromagnetic brakeCHand brakeDMotor controller