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
Which device is designed to automatically hold the load if power should fail to an electric winch?
A.Pneumatic brake
B.Electromagnetic brake
C.Hand brake
D.Motor controller
相关考题：
Which command is used to restore a Junos device to its default state?() A. load factory-defaultB. load override factory-defaultC. load replace defaultD. load set default
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
Running an electric winch at slow speed over a long period of time causes ______．A.the speed to be retarded by the friction brakeB.a load to go downward at full speedC.the circuit breaker to turn offD.the resistors to overheat and eventually burn out
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
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
If a hydraulic pump on a winch accidentally stops while hoisting, the load will stay suspended because______.A.a check valve will close that prevents reverse circulationB.a centrifugal counterweight counteracts the force of gravityC.the electric pump motor will cut outD.the control lever will move to the stop position
Which configuration should be done in order to improve the performance of the Cisco Unified Wireless IP Phone 7921G in a WLAN infrastructure?（）A、enable aggressive load balancingB、enable coverage hole detectionC、disable dynamic transmit power controlD、enable short preamble
If a technician suspects that the voltage being delivered to a desktop computer’s power supply is insufficient or incorrect, which device should be used to determine the correct voltage?（）A、A power supply testerB、A multimeterC、A loopback adapterD、A cable tester
When configuring a wlan controller for a voice application using cisco 7920 wireless ip phones. which two general control settings should you select？（）A、multicast onB、aggressive load balancing offC、multicast offD、ap fallback onE、aggressive load balancing onF、ap fallback off
When configuring a WLAN controller for a voice application using Cisco 7920 wireless IP phones，which two general control settings should you select？（）A、Aggressive Load Balancing onB、Aggressive Load Balancing offC、Multicast onD、Multicast offE、AP Fallback onF、AP Fallback off
Which of the following is the MOST likely to cause a server power supply fan to fail but allows the power supply to still be functional？（）A、DustB、Power SurgeC、Excessive humidityD、High temperatures
Which command is used to restore a Junos device to its default state?（）A、load factory-defaultB、load override factory-defaultC、load replace defaultD、load set default
单选题If the winch should fail while you are hauling in the anchor，what prevents the anchor cable from running out?（）AChain stopperBDevil's clawCHawse ratchetDRiding pawl
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A mechanical davit is designed to automatically（）.Aposition the boat at the embarkation stationBlift the boat off the inboard chocksCenergize the winch for the fallsDset the brake on the winch
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
单选题A rigid lifesaving device only designed for survivors to hold on to while in the water is a（）.AliferaftBlife floatClife preserverDbuoyant apparatus
多选题When configuring a wlan controller for a voice application using cisco 7920 wireless ip phones. which two general control settings should you select？（）Amulticast onBaggressive load balancing offCmulticast offDap fallback onEaggressive load balancing onFap fallback off
多选题When configuring a WLAN controller for a voice application using Cisco 7920 wireless IP phones，which two general control settings should you select？（）AAggressive Load Balancing onBAggressive Load Balancing offCMulticast onDMulticast offEAP Fallback onFAP Fallback off
单选题Electric cargo winches have an overload safety device which normally cuts the current to the winch motor（）.Aafter torque cause 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 strengh of the fallDbefore the safe working load of the fall is reached
单选题If a technician suspects that the voltage being delivered to a desktop computer’s power supply is insufficient or incorrect, which device should be used to determine the correct voltage?（）AA power supply testerBA multimeterCA loopback adapterDA cable tester
单选题Adjustments to the compensating needle valve in a hydraulic governor should be made with the engine at （）Amaximum power at a normal loadBmaximum power and load under normal conditionsChalf speed and normal temperatureDnormal operating temperature without a load
单选题What provides autos with electric power in an automated highway system?AA rail.BAn engine.CA retractable arm.DA computer controller.
单选题Which will cause a wire rope to fail（）.AUsing a medium graphite grease as a lubricantBOperating a winch too slowCUsing a sheave with an undersized throatDA sheave diameter of 24 times the wire's diameter
单选题The drive motor will have a brake arranged to fail-safe, ieit will （） the load if power fails or machine is stopped.AliftBputCtakeDhold
单选题Which of the following is the MOST likely to cause a server power supply fan to fail but allows the power supply to still be functional？（）ADustBPower SurgeCExcessive humidityDHigh temperatures
单选题The drive motor will have a brake arranged to fail-safe, i√eit will （） the load if power fails or machine is stopped.AcastBputCholdDlet out