The meat box temperature control circuit, as used in the ship service refrigeration system, is an example of ______.A.two position controlB.single speed floating controlC.proportional(比例) controlD.reset control

题目

The meat box temperature control circuit, as used in the ship service refrigeration system, is an example of ______.

A.two position control

B.single speed floating control

C.proportional(比例) control

D.reset control

相似考题

1.For (71) service, we need a virtual-circuit subnet. Let us see how that works. The idea behind virtual circuits is to avoid having to choose a new (72) for every packet sent. Instead, when a connection is established, a route from the (73)machine to the destination machine is chosen as part of the connection setup and stored in tables inside the (74) That route is used for all traffic flowing over the connection, exactly the same way that the telephone system works. When the connection is released, the virtual circuit is also terminated. With connection-oriented service, each packet carries an (75) telling which virtual circuit it belongs to.A．connectionlessB．connection-orientedC．datagramD．telegram

2.第一组An automatic system usually consists of a control system and an information system. A control system is a system which measures the condition of some entity and, with the information, governs the state of a variable; i.e., speed, temperature, pressure, position, etc. The open-loop system is the simplest form. a control system may assume. It is distinguished from the closed-loop system by the lack of an input which measures the state of the controlled variable; such an input is called a feedback. In modern ships the open-loop system has practically disappeared and the closed-loop system which operates with a feed-back is extensively used. An information system serves the parallel function of monitoring system or plant performance. The monitoring function may serve a number of purposes; specifically it may indicate values of controlled variables to guide remote control operations, warn of off-limit conditions and provide record of performance. In many cases a visual and audible alarm may be provided to warn of off-limit conditions on board ship and, associated with this, the important variables will be recorded on demand. The automatic control system can be more sophisticated by incorporating digital-processing equipment, that is, a computer. This computer is usually fed with signals from all sensors. It scans the values of the sensors and generates alarm signals for off-limit conditions, acting as a super-supervisor. Sometimes, it can even make necessary and take the necessary action to optimize performance without human intervention.The closed-loop system differs from the open-loop system byA.the lack of a feedbackB.the presence of a feed backC.the lack of a computerD.the presence of a computer

3.The part of the shipboard electrical system used to control the distribution of power to the branch circuits, is the ______.A.bridge control panelB.disconnect linksC.main switchboardD.governor relay box

4.The expansion valve used in a refrigeration system regulates theA.superheat of the gas leaving the compressorB.back pressure in the evaporatorC.temperature in the refrigerated spaceD.degree of superheat of the gas leaving the evaporator

更多“The meat box temperature control circuit, as used in the ship service refrigeration system ”相关问题

  • 第1题：

    The sensing line for the low pressure cutout switch to a refrigeration system is located ______.

    A.in the chill box(冰箱)

    B.before the receiver

    C.on the suction side of the compressor

    D.on the discharge side of the compressor


    正确答案：C

  • 第2题：

    Excessive circulation of the lubricating oil with the refrigerant in a refrigeration system will cause______.

    A.carbon deposits on the compressor suction valves

    B.the evaporator temperature to increase

    C.rapid corrosion of the thermal expansion valve

    D.no operating problems


    正确答案：B

  • 第3题：

    单选题
    （）on board ship are used to control and distribute the electrical energy generated by generators.
    A

    Governors

    B

    Alternators

    C

    Blackboards

    D

    Switchboards


    正确答案： D
    解析： 暂无解析

  • 第4题：

    单选题
    For (1) service, we need a virtual-circuit subnet. Let us see how that works. The idea behind virtual circuits is to avoid having to choose a new (2) for every packet sent. Instead,when a connection is established, a route from the(3) machine to the destination machine is chosen as part of the connection setup and stored in tables inside the (4) . That route is used for all traffic flowing over the connection, exactly the same way that the telephone system works.When the connection is released, the virtual circuit is also terminated. With connection-oriented service, each packet carries an (5) telling which virtual circuit it belongs to. 空白（3）处应选择（）
    A

    source

    B

    route

    C

    destination

    D

    host


    正确答案： B
    解析： 对于面向连接的服务，我们需要一个虚拟电路子网。让我们看看它是如何工作的。虚电路的核心思想是避免在发送每个数据时为它们选择一个新的路由。相反，当建立一个连接，将从源计算机向目标计算机选择一条路由作为连接设置的一部分并且存储到内部的路由器表中。这条路由承载着所有连接带来的流量，就跟电话系统的工作原理一样。当连接被释放时，虚电路也终止。在面向连接的服务中，每个数据包携带一个标识符，该标识符告诉它所属的虚电路。

  • 第5题：

    单选题
    An excessive charge of refrigerant in an air-cooled refrigeration system can cause （）.
    A

    oil foaming in the compressor

    B

    higher than normal suction and discharge pressures with a higher box temperature

    C

    higher than normal discharge pressure with a normal box temperature

    D

    the compressor to run continuously


    正确答案： C
    解析： 暂无解析

  • 第6题：

    单选题
    （） is used for sensing the temperature of the room in the air condition system.
    A

    An expansion valve

    B

    An evaporator

    C

    A thermostat

    D

    A condenser


    正确答案： A
    解析： 暂无解析

  • 第7题：

    单选题
    Moisture in a refrigeration system can cause （）.
    A

    freezing the expansion valve closed

    B

    corrosion of system piping

    C

    improper temperature regulation

    D

    all of the above


    正确答案： C
    解析： 暂无解析

  • 第8题：

    单选题
    Which of the following methods is normally used to control the temperature of air distributed from individual cooling coils in an air conditioning system using a chilled water circulation system?（）
    A

    A room thermostat activates an electric heater at each individual chilled air outlet when necessary

    B

    Varying the number of passes the air makes across the coils

    C

    Varying the temperature of the water through the coils

    D

    Varying the quantity of water flowing through the coils


    正确答案： B
    解析： 暂无解析

  • 第9题：

    单选题
    A solenoid valve used in a refrigeration system should be installed （）.
    A

    with the axis of the solenoid horizontal, sensing temperature of the box, and upstream of the thermal expansion valve

    B

    upright, sensing temperature of the box, and upstream of the thermal expansion valve

    C

    upright, sensing temperature of the box, and downstream of the thermal expansion valve

    D

    upright, sensing heat of the tail coil, and upstream of the thermal expansion valve


    正确答案： D
    解析： 暂无解析

  • 第10题：

    单选题
    Compensated flow control or constant flow valves are used in hydraulic systems to（）
    A

    compensate for major leaks in the system

    B

    maintain the original fluid viscosity

    C

    allow for changes in pressure and temperature within the system

    D

    assure constant fluid temperature


    正确答案： D
    解析： 暂无解析

  • 第11题：

    单选题
    The meat box temperature control circuit, as used in ship service refrigeration system, is an example of （）
    A

    two position control

    B

    signal speed floating control

    C

    proportional control

    D

    reset control


    正确答案： B
    解析： 暂无解析

  • 第12题：

    单选题
    If an air compressor is used to supply air primarily to the combustion control system and other pneumatic controllers, the entire system is known as the （）.
    A

    control air system

    B

    forced draft air system

    C

    supply air system

    D

    ships service air system


    正确答案： A
    解析： 暂无解析

  • 第13题：

    An increase in the heat load to a refrigeration system will cause ______.

    A.the suction pressure to decrease

    B.the suction temperature to increase

    C.increased ice formation on the evaporator coil

    D.excessive short cycling of the compressor


    正确答案：B

  • 第14题：

    单选题
    In a direct expansion type multi-box refrigeration system, the compressor is set up to cycle on and off by the（）
    A

    pressurestat

    B

    high pressure cutout

    C

    solenoid valve

    D

    low pressure cutout switch


    正确答案： B
    解析： 暂无解析

  • 第15题：

    单选题
    A re-heater, as used in an air conditioning system, is designed to control the （）
    A

    chilled water temperature

    B

    dew point temperature

    C

    primary air temperature

    D

    dry bulb temperature


    正确答案： D
    解析： 暂无解析

  • 第16题：

    单选题
    Which of the following statements is correct concerning a typical shipboard multi-coil refrigeration system?（）
    A

    The liquid receiver functions to collect and remove non-condensable gases

    B

    A thermostatic expansion valve is used to control refrigerated space temperature

    C

    Refrigerant temperature in an evaporator is directly related to refrigerant pressure

    D

    Dehydrators must be used continuously in a refrigeration system


    正确答案： C
    解析： 暂无解析

  • 第17题：

    单选题
    Thermostatic steam pressure reducing valves are used in the fuel oil service system to control the（）
    A

    double bottom fuel oil tank temperature

    B

    heater supply steam flow

    C

    pressure of the fuel supplied to the burners

    D

    attemperator steam flow in the heater discharge circuit


    正确答案： D
    解析： 暂无解析

  • 第18题：

    单选题
    The refrigerant leaves the evaporator of a refrigeration system as a low pressure （）.
    A

    sub-cooled liquid

    B

    high temperature liquid

    C

    oil saturated liquid

    D

    superheated vapor


    正确答案： B
    解析： 暂无解析

  • 第19题：

    单选题
    If an air compressor is used to supply compressed air to outlets throughout the engine room and on deck of a vessel, the system is known as the （）.
    A

    combustion control air system

    B

    supply air system

    C

    ships service air system

    D

    low pressure deck air system


    正确答案： D
    解析： 暂无解析

  • 第20题：

    单选题
    An increase in the heat load to a refrigeration system will cause （）.
    A

    the suction pressure to decrease

    B

    the suction temperature to increase

    C

    increased ice formation on the evaporator coil

    D

    excessive short cycling of the compressor


    正确答案： A
    解析： 暂无解析

  • 第21题：

    单选题
    Which of the listed statements is correct concerning refrigeration systems?（）
    A

    Dehydrators must be used continuously in a refrigeration system

    B

    A 25 ton refrigeration system has the same cooling effect as melting 25 tons of ice in 24 hours

    C

    A thermostatic expansion valve is used to control refrigerated space temperature

    D

    The liquid receiver functions to collect and remove non- condensable gases


    正确答案： A
    解析： 暂无解析

  • 第22题：

    单选题
    What is NOT an advantage of the house-fall system when compared to a married-fall system using two of the ship’s booms? （）
    A

    There is a steady spotting area under the dockside block

    B

    Loading can be accomplished from a narrow apron without endangering the inboard boom

    C

    The system can be used for working the second deck of a warehouse

    D

    There is more accurate control of cargo drafts required to be stowed in the wings


    正确答案： D
    解析： 暂无解析

  • 第23题：

    单选题
    The receiver used in a refrigeration system（）
    A

    stores liquid refrigerant

    B

    collects non-condensable gases

    C

    allows refrigerant sub-cooling

    D

    prevents compressor surging


    正确答案： A
    解析： 暂无解析

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