樓宇自控系統(tǒng)設(shè)計(jì)外文翻譯

1、<p><b>　　外文資料</b></p><p>　　Energy-saving solution for commercial buildings</p><p>　　Commercial buildings energy-saving solution for the status quo of China's electricity ind

2、ustry government agencies, enterprises, universities, hotels, hospitals and other buildings have we can not ignore the cost, that is, high tariffs, and we often spend a lot of energy through administrative means to Energ

3、y management and energy conservation announced </p><p>　　Analog-to-digital (A/D) converter: The part of a microprocessor- based controller that changes an analog input signal to a digital value for use by th

4、e microprocessor in executing software programs. Analog input values typically come from temperature, pressure, humidity, or other types of sensors or transducers.</p><p>　　Application software: Programs tha

5、t provide functions such as direct digital control, energy management, lighting control, event initiated operations, and other alarm and monitoring routines.</p><p>　　Configurable controller: A controller wi

6、th a set of selectable programs with adjustable parameters but without the ability to modify the programs.</p><p>　　Digital-to-analog (D/A) converter: The part of a microprocessor- based controller that chan

7、ges digital values from a software program to analog output signals for use in the control system. The analog signals are typically used to position actuators or actuate transducers and relays.</p><p>　　Dire

8、ct digital control: A control loop in which a digital controller periodically updates a process as a function of a set of measured control variables and a given set of control algorithms.</p><p>　　Microproce

9、ssor-based controller: A device consisting of a microprocessor unit, digital input and output connections, A/D and D/A converters, a power supply, and software to perform direct digital control and energy management rout

10、ines in a HVAC system.</p><p>　　Operating software: The main operating system and programsthat schedule and control the execution of all otherprograms in a microprocessor-based controller. This includes rout

11、ines for input/output (I/O) scanning, A/D and D/A conversion, scheduling of application programs, and access and display of control program</p><p>　　variables.</p><p>　　System-level controller:

12、A microprocessor-based controller that controls centrally located HVAC equipment such as variable air volume (VAV) supply units, built-up</p><p>　　air handlers, and central chiller and boiler plants. These c

13、ontrollers typically have a library of control programs, may control more than one mechanical system from a</p><p>　　single controller, and may contain an integral operating terminal.</p><p>　　Z

14、one-level controller: A microprocessor-based controller that controls distributed or unitary HVAC equipment such as VAV terminal units, fan coil units, and heat pumps. These controllers typically have relatively few conn

15、ected I/O devices, standard control sequences, and are dedicated to specific applications.</p><p>　　BACKGROUND</p><p>　　COMPUTER BASED CONTROL</p><p>　　Computer based control system

16、s have been available as an alternative to conventional pneumatic and electronic systems since the mid 1960s. Early installations required a central mainframe or minicomputer as the digital processing unit. They were exp

17、ensive, and application was limited to larger buildings. Reliability was also an issue since loss of the central computer meant loss of the entire control system. Advances in microtechnology, particularly in large scale

18、integration (LSI), provided ans</p><p>　　A more detailed definition is provided in the ASHRAE 1995 HVAC Applications Handbook. “A digital controller can be either single- or multiloop. Interface hardware all

19、ows the digital computer to process signals from various input devices, such as the electronic temperature, humidity, and pressure sensors described in the section on Sensors. Based on the digitized equivalents of the vo

20、ltage or current signals produced by the inputs, the control software calculates the required state of the output </p><p>　　In each of these definitions the key element for DDC is digital computation. The mi

21、croprocessor unit (MPU) in the controller provides the computation. Therefore, the term digital in DDC refers to digital processing of data and not that HVAC sensor inputs or control outputs from the controller are neces

22、sarily in digital format. Nearly all sensor inputs are analog and most output devices are also analog. In order to accept signals from these I/O devices, A/D and D/A converters are included in the </p><p>　　

23、DIRECT DIGITAL CONTROL</p><p>　　Inherent in microprocessor-based controllers is the ability toperform direct digital control. DDC is used in place ofconventional pneumatic or electronic local control loops.

24、Thereare several industry accepted definitions of DDC. DDC can be defined as “a control loop in which a digital controllerperiodically updates a process as a function of a set of measuredcontrol variables and a given set

25、 of control algorithms”.</p><p>　　ADVANTAGES</p><p>　　Digital control offers many advantages. Some of the moreimportant advantages are discussed in the following.</p><p>　　LOWER COS

26、T PER FUNCTION</p><p>　　In general, microprocessor and memory costs keep coming down while inherent functionality keeps going up. Compared to earlier systems, physical size of the controller is also reduced

27、while the number of discrete functions is increased.</p><p>　　Digital control, using a microcomputer-based controller, allows more sophisticated and energy efficient control sequences to be applied at a lowe

28、r cost than with non-digital controls; however, simple applications are less costly with non-digital controls.</p><p>　　APPLICATION FLEXIBILITY</p><p>　　Since microprocessor-based controllers ar

29、e software based, application flexibility is an inherent feature. A wide variety of HVAC functions can be programmed and, in addition, the controller can perform energy management, indoor air quality (IAQ), and/or buildi

30、ng management functions. Changes in control sequences can easily be accommodated through software whether dictated by system performance or by changes in the owner’s use of the facility.</p><p>　　COORDINATED

31、 MULTIFUNCTION CAPABILITY</p><p>　　Although basic environmental control and energy management operate as independent programs, it is best to have them incorporated as an integrated program in order to provid

32、e more efficient control sequences. For example, sensing the temperatures of several zones to determine the average demand, or the zone with the greatest demand for cooling, will provide improved efficiency and control o

33、ver merely sampling a representative zone for a chiller reset program. An added feature is that the sensors </p><p>　　PRECISE AND ACCURATE CONTROL</p><p>　　Proportional control has the inherent

34、problem of offset. The wider the throttling range is set for control stability, the greater the offset. With the microprocessor-based controller, the offset can easily be corrected by the simple addition of integral acti

35、on.</p><p>　　For even more accurate control over a wide range of external conditions, adaptive control algorithms, available in some microprocessor-based controllers, can be employed. With adaptive control,

36、system performance automatically adjusts as conditions vary. The need for manual fine tuning for seasonal changes is eliminated. These items are discussed in the Control Fundamentals section.</p><p>　　RELIAB

37、ILITY</p><p>　　Digital controllers should be conservatively designed and should incorporate self-checking features so they notify the operator immediately if anything goes wrong. Input and output circuits sh

38、ould be filtered and protected from extraneous signals to assure reliable information to the processor.</p><p>　　CONTROLLER CONFIGURATION</p><p>　　The basic elements of a microprocessor-based (o

39、r microprocessor)</p><p>　　controller (Fig. 3) include:</p><p>　　— The microprocessor</p><p>　　— A program memory</p><p>　　— A working memory</p><p>　　— A

40、clock or timing devices</p><p>　　— A means of getting data in and out of the system</p><p>　　In addition, a communications port is not only a desirable feature but a requirement for program tuni

41、ng or interfacing with a central computer or building management system. Timing for microprocessor operation is provided by a batterybacked clock. The clock operates in the microsecond range controlling execution of prog

42、ram instructions.</p><p>　　Program memory holds the basic instruction set for controller operation as well as for the application programs. Memory size and type vary depending on the application and whether

43、the controller is considered a dedicated purpose or general purpose device. Dedicated purpose configurable controllers normally have standard programs and are furnished with read only memory (ROM) or programmable read on

44、ly memory (PROM.) </p><p>　　General purpose controllers often accommodate a variety of individual custom programs and are supplied with field-alterable memories such as electrically erasable, programmable, r

45、ead only memory (EEPROM) or flash memory. Memories used to hold the program for a controller must be nonvolatile, that is, they retain the program data during power outages.</p><p>　　All input signals, wheth

46、er analog or digital, undergo conditioning to eliminate the adverse affects of contact bounce, induced voltage, or electrical transients. Time delay circuits, electronic filters, and optical coupling are commonly used fo

47、r this purpose. Analog inputs must also be linearized, scaled, and converted to digital values prior to entering the microprocessor unit. Resistance sensor inputs can also be compensated for leadwire resistance. For addi

48、tional information about electronic </p><p>　　Performance and reliability of temperature control applications can be enhanced by using a single 12-bit A/D converter for all controller multiplexed inputs, and

49、 simple two-wire high resistance RTDs as inputs.</p><p>　　A/D converters for DDC applications normally range from 8 to 12 bits depending on the application. An 8-bit A/D converter provides a resolution of on

50、e count in 256. A 12-bit A/D converter provides a resolution of one count in 4096. If the A/D converter is set up to provide a binary coded decimal (BCD) output, a 12-bit converter can provide values from 0 to 999, 0 to

51、99.9, or 0 to 9.99 depending on the decimal placement. This range of outputs adequately covers normal control and display ranges fo</p><p>　　The output multiplexer provides the reverse operation from the inp

52、ut multiplexer. It takes a serial string of output values from the D/A converter and routes them to the terminals connected to a transducer or a valve or damper actuator.</p><p>　　The communication port (Fig

53、. 3) allows interconnection of controllers to each other, to a master controller, to a central computer, or to local or portable terminals.</p><p>　　TYPES OF CONTROLLERS</p><p>　　Microprocessor-

54、based controllers operate at two levels incommercial buildings: the zone level and the system level. </p><p>　　ZONE-LEVEL CONTROLLER</p><p>　　Zone-level controllers typically control HVAC termin

55、al units that supply heating and cooling energy to occupied spaces and other areas in the building. They can control VAV terminal units, fan coil units, unit ventilators, heat pumps, space pressurization equipment, labor

56、atory fume hoods, and any other zone control or terminal unit device. Design of a zone-level controller is usually dictated by the specific requirements of the application. For example, the controller for a VAV box is fr

57、equently</p><p>　　SYSTEM-LEVEL CONTROLLER</p><p>　　System-level controllers are more flexible than zone-level controllers in application and have more capacity. Typically, system-level controlle

58、rs are applied to systems in equipment rooms including VAV central supply systems, built-up air handlers, and central chiller and boiler plants. Control sequences vary and usually contain customized programs written to h

59、andle the specific application requirements.</p><p>　　The number of inputs and outputs required for a system-level controller is usually not predictable. The application of the controller must allow both the

60、 number and mix of inputs and outputs to be variable. Several different packaging approaches have been used:</p><p>　　— Fixed I/O configuration.</p><p>　　— Universal I/O configuration.</p>

61、;<p>　　— Card cage with plug-in function boards.</p><p>　　Universal I/O allows software to define the function of each set of terminals.</p><p>　　Zone- and system-level controllers should

62、 be equipped with a communications port. This allows dynamic data, setpoints, and parameters to be passed between a local operator terminal, a central building management system, and/or other controllers. Data passed to

63、other controllers allows sensor values to be shared and interaction between zone-level programs and system-level programs to be coordinated. For example, night setback and morning warmup can be implemented at the zonelev

64、el controller based</p><p>　　TYPICAL APPLICATIONS</p><p>　　ZONE-LEVEL CONTROLLER</p><p>　　Zone-level controllers can be applied to a variety of types of HVAC unitary equipment. Seve

65、ral control sequences can be resident in a single zone-level controller to meet various application requirements. The appropriate control sequence is selected and set up through either a PC for the system or through a po

66、rtable operator’s terminal. The following two examples discuss typical control sequences for one type of zone-level controller used specifically for VAV air terminal units. For further info</p><p>　　EXAMPLE

67、1. VAV COOLING ONLY</p><p>　　In a pressure independent VAV cooling only air terminal unit application the zone-level controller controls the primary airflow independent of varying supply air pressures. The a

68、irflow setpoint of the controller is reset by the thermostat to vary airflow between field programmable minimum and maximum settings to satisfy space temperatures. On a call for less cooling, the damper modulates toward

69、minimum. On a call for more cooling, the damper modulates toward maximum. The airflow control maintain</p><p>　　EXAMPLE 2. VAV COOLING WITH SEQUENCED ELECTRIC REHEAT</p><p>　　In a VAV cooling ai

70、r terminal unit application with sequenced electric reheat, an adjustable deadband is provided between the cooling and the reheat cycle. During cooling the control mode is constant discharge temperature, variable volume.

71、 On a call for less cooling, the damper modulates toward minimum flow. The damper remains at minimum cooling through a deadband. On a call for reheat, the damper goes from minimum flow to reheat flow to ensure proper air

72、 distribution and prevent excessively hig</p><p>　　SYSTEM-LEVEL CONTROLLER</p><p>　　System-level controllers are variable-function devices applied to a wide variety of mechanical systems. These

73、controllers can accommodate multiloop custom control sequences and have control integrated with energy management and building management functions. The examples that follow cover direct digital control functions for a s

74、ystem-level controller. Integrated building management functions are covered in the Building Management System Fundamentals section.</p><p>　　Where the examples indicate that user entered values are furnishe

75、d (e.g., setpoint), or that key parameters or DDC operator outputs will have display capability, this represents sound software design practice and applies whether or not the controller is tied into a central building ma

76、nagement system. Data is entered or displayed in non-BMS applications by a portable operator’s terminal or by a keypad when display is integral with the controller.</p><p>　　A three-step approach can be used

77、 to define DDC programs.</p><p>　　1. Develop a system flow schematic as a visual representation of the process to be controlled. The schematic may be provided as a part of the plans and specifications for th

78、e job. If not, a schematic must be created for the system.</p><p>　　2. Add actuators, valves, sensors, setpoints, and operational data required for control and operation.</p><p>　　3. Write a det

79、ailed sequence of operation describing the</p><p>　　relationship between inputs, outputs, and operational</p><p>　　data points.</p><p>　　An example of this approach follows for cont

80、rol of a hot water converter：</p><p>　　Step 1—Develop flow schematic of the process to be controlled</p><p>　　Refer to the Control Fundamentals section for a symbol legend.</p><p>　

81、　Step 2—Identify required sensors, actuators, and operationaldata </p><p>　　If the DDC system is provided with a BMS having a colormonitor, a graphic may be required to be displayed with live, displayable an

82、d commandable points (12 total). If a BMS is not provided, the points may be required to be displayed on a text terminal (fixed or portable) at the system level controller</p><p><b>　　.</b></p

83、><p>　　Step 3—Write a detailed sequence of operation for the process.</p><p>　　The hot water pump starts anytime the outside air temperature drops to 52F, subject to a software on-off-auto function

84、. </p><p>　　When hot water pumping is proven by a current sensitive relay, converter controls are energized. Hot water temperature setpoint varies linearly from 120F to 170F as the outside air temperature va

85、ries from 60F to 0F. The converter steam valve is modulated to maintain a converter leaving water temperature according to a varying setpoint schedule.</p><p>　　The steam valve closes anytime hot water pumpi

86、ng is not proven and anytime the valve actuator loses motive power.</p><p><b>　　中文翻譯</b></p><p><b>　　導(dǎo)言</b></p><p>　　本文談?wù)撚糜谏虡I(yè)大廈的根據(jù)微處理機(jī)的控制器的種類(lèi)。 這些控制器在這個(gè)部分在商業(yè)大

87、廈談?wù)摳鶕?jù)微處理機(jī)的控制器的種類(lèi)使用的介紹測(cè)量信號(hào)從傳感器，執(zhí)行控制代碼。 這些控制器在軟件程序測(cè)量信號(hào)從傳感器，執(zhí)行控制代碼，并且采取懲治行為以輸出信號(hào)的形式對(duì)作動(dòng)器。 因?yàn)楣?jié)目以數(shù)字式形式，控制器執(zhí)行什么通認(rèn)作為直接數(shù)字控制(DDC)。 根據(jù)微處理機(jī)的控制器可以使用作為獨(dú)立控制器或他們可以使用作為控制器被合并到運(yùn)用個(gè)人計(jì)算機(jī)的房屋管理系統(tǒng)里(個(gè)人計(jì)算機(jī))作為主人提供另外的作用。一個(gè)獨(dú)立控制器可能采取幾個(gè)形式。 當(dāng)更大的版本可能控制從

88、八個(gè)到40個(gè)控制回路時(shí)，最簡(jiǎn)單只一般控制一個(gè)控制回路。 當(dāng)系統(tǒng)得到更大，他們一般合并更多編程的特點(diǎn)和作用。這個(gè)部分表明控制器作為一個(gè)獨(dú)立單位。 參見(jiàn)房屋管理系統(tǒng)根本性部分為其它信息關(guān)于對(duì)控制器的用途在網(wǎng)絡(luò)和房屋管理系統(tǒng)。</p><p><b>　　定義</b></p><p>　　從模擬式到數(shù)字式的(A/D)交換器： 在執(zhí)行軟件程序改變一個(gè)模擬輸入信號(hào)到數(shù)字式價(jià)值供

89、微處理器使用微處理器基于控制器的部分。 模擬輸入價(jià)值典型地來(lái)自溫度、壓力、濕氣，或者傳感器或變換裝置的其他類(lèi)型。</p><p>　　應(yīng)用軟件： 提供作用這樣作為直接數(shù)字控制，能量消耗監(jiān)控，點(diǎn)燃控制的節(jié)目，事件創(chuàng)始操作和其他警報(bào)和執(zhí)行程序。</p><p>　　構(gòu)形的控制器： 一個(gè)控制器與一套可選擇的項(xiàng)目以可調(diào)參數(shù)，但沒(méi)有能力修改項(xiàng)目。</p><p>　　數(shù)字模擬

90、(D/A)交換器： 從軟件程序改變數(shù)字式價(jià)值到模擬輸出微處理器基于控制器的部分發(fā)信號(hào)用于控制系統(tǒng)。 模擬信號(hào)典型地使用安置作動(dòng)器或開(kāi)動(dòng)變換裝置和中轉(zhuǎn)。</p><p>　　直接數(shù)字控制： 一個(gè)數(shù)字控制器周期性地更新過(guò)程的控制回路，一套被測(cè)量的控制變量和特定套的作用控制算法。</p><p>　　基于微處理機(jī)的控制器： 包括微處理器的設(shè)備、數(shù)字輸入和產(chǎn)品連接、A/D和D/A交換器、電源和軟件

91、執(zhí)行直接數(shù)字控制和能量消耗監(jiān)控慣例在HVAC系統(tǒng)。</p><p>　　運(yùn)行的軟件： 主要操作系統(tǒng)和項(xiàng)目日程表和在一個(gè)根據(jù)微處理機(jī)的控制器控制</p><p>　　其他項(xiàng)目的施行。 這包括慣例為輸入-輸出(輸入/輸出)掃描， A/D和D/A轉(zhuǎn)換，預(yù)定應(yīng)用程序和控制程序可變物通入和顯示。</p><p>　　系統(tǒng)級(jí)控制器： 中央控制找出HVAC設(shè)備這樣作為易變的空氣容

92、積的一個(gè)根據(jù)微處理機(jī)的控制器(VAV)供應(yīng)單位、組合空氣經(jīng)理和中央致冷物和鍋爐植物。 這些控制器典型地有控制程序圖書(shū)館，也許控制超過(guò)一個(gè)機(jī)械系統(tǒng)從一個(gè)唯一控制器，并且也許包含一個(gè)缺一不可的經(jīng)營(yíng)的終端。</p><p>　　區(qū)域級(jí)控制器： 控制分布或單一的HVAC設(shè)備這樣當(dāng)VAV終端設(shè)備、風(fēng)扇卷單位和熱泵的一個(gè)根據(jù)微處理機(jī)的控制器。這些控制器典型地有相對(duì)地少量連接的輸出入裝置，標(biāo)準(zhǔn)控制序列和致力具體應(yīng)用。</

93、p><p><b>　　背景</b></p><p>　　計(jì)算機(jī)為主的控制基于計(jì)算機(jī)的控制系統(tǒng)是可利用的作為選擇對(duì)常規(guī)氣動(dòng)力學(xué)和電子系統(tǒng)從60年代中期。 早期的設(shè)施要求一臺(tái)中央計(jì)算機(jī)主機(jī)或微型計(jì)算機(jī)作為數(shù)字式處理器。 他們是昂貴的，并且應(yīng)用被限制了到更大的大廈。因?yàn)橹醒胗?jì)算機(jī)的損失意味整個(gè)控制系統(tǒng)的損失，可靠性也是問(wèn)題。特別在大規(guī)模集成(LSI)，假設(shè)答復(fù)對(duì)費(fèi)用和可靠性問(wèn)

94、題。 微處理器的介紹，即，一臺(tái)計(jì)算機(jī)在芯片和高密度記憶減少的費(fèi)用和包裹大小顯著和增加的應(yīng)用靈活性. 微處理器節(jié)目包括大規(guī)模計(jì)算機(jī)的所有算術(shù)、邏輯和控制元素，因而提供計(jì)算能力在性價(jià)比比率適當(dāng)為應(yīng)用對(duì)各自的空氣經(jīng)理、熱泵、VAV終端設(shè)備或者整個(gè)設(shè)備屋子。</p><p>　　根據(jù)微處理機(jī)的控制器允許數(shù)字控制被分布在區(qū)域水平，設(shè)備室水平，或者他們可以控制一個(gè)整個(gè)大廈。</p><p>　　更詳細(xì)

95、的定義，是提供在該ashrae 1995年暖通空調(diào)的應(yīng)用手冊(cè)。 “數(shù)字控制器可以無(wú)論是單或多。硬件接口，讓數(shù)字電腦的過(guò)程中的信號(hào)來(lái)自不同的輸入設(shè)備，如作為電子溫度，濕度，和壓力傳感器節(jié)所述，對(duì)傳感器。的基礎(chǔ)上，數(shù)字化等值的電壓或電流信號(hào)所產(chǎn)生的投入，控制軟件的計(jì)算需要國(guó)家的輸出設(shè)備，如閥門(mén)和阻尼器的致動(dòng)器和風(fēng)扇首發(fā)。輸出設(shè)備，然后轉(zhuǎn)移到計(jì)算的立場(chǎng)，透過(guò)硬體介面，轉(zhuǎn)換成數(shù)字信號(hào)從計(jì)算機(jī)模擬電壓或電流的要求立場(chǎng)動(dòng)或活力中繼“ 。</p

96、><p>　　在上述每個(gè)定義的關(guān)鍵要素的DDC是數(shù)字計(jì)算。微處理器單元（微處理器） ，在控制器提供了計(jì)算。因此，長(zhǎng)遠(yuǎn)的數(shù)字在DDC的是指數(shù)字化處理的數(shù)據(jù)和暖通空調(diào)傳感器或控制的投入產(chǎn)出從控制器一定要在數(shù)字格式。幾乎所有的傳感器的輸入模擬和大多數(shù)輸出設(shè)備，也模擬。在以接受信號(hào)從這些I / O設(shè)備， A / D和D / A轉(zhuǎn)換器是包括在微處理器為基礎(chǔ)的控制器。</p><p><b>　

97、　直接數(shù)字控制</b></p><p>　　固有的基于微處理器的控制器是能力執(zhí)行直接數(shù)字控制。 DDC的是用來(lái)取代常規(guī)氣動(dòng)或電子控制回路的地方。那里有幾個(gè)行業(yè)接受的定義， DDC的。 DDC的可定義為“控制回路的一個(gè)數(shù)字控制器定期更新的過(guò)程，作為一個(gè)功能的一套測(cè)量控制變量和一組給定的控制算法“ 。</p><p><b>　　優(yōu)勢(shì)</b></p>

98、;<p>　　數(shù)字控制提供了許多優(yōu)勢(shì)。一些較重要的優(yōu)勢(shì)是討論如下</p><p>　　以較低的成本實(shí)現(xiàn)功能</p><p>　　在一般來(lái)說(shuō)，微處理器和記憶體的成本保持未來(lái)而內(nèi)在功能不斷持續(xù)上升。相比較早前系統(tǒng)，物理大小控制器也減少，而有多少離散的職能是有所增加。數(shù)字控制，采用微機(jī)型控制器，允許更精密及具能源效益的控制序列，以適用于以較低的成本比與非數(shù)字化控制;不過(guò)，簡(jiǎn)單的申請(qǐng)

99、費(fèi)用較低的與非數(shù)字化控制。</p><p><b>　　應(yīng)用靈活性</b></p><p>　　由于基于微處理器的控制器都是基于軟件，應(yīng)用的靈活性，是一種內(nèi)在功能。各種各樣的暖通空調(diào)功能，可以編程，此外，該控制器可以執(zhí)行能源管理，室內(nèi)空氣質(zhì)量（室內(nèi)空氣品質(zhì)） ，和/或大廈管理職能。的變化，在控制序列可輕易容納通過(guò)軟件是否出于系統(tǒng)性能，或變化，在業(yè)主的設(shè)施的使用。<

100、;/p><p><b>　　多功能協(xié)調(diào)能力</b></p><p>　　雖然基本控制環(huán)境污染和能源管理運(yùn)作，作為獨(dú)立的程序，最好是把他們納入作為一個(gè)綜合計(jì)劃，以便提供更有效的控制序列。舉例來(lái)說(shuō)，溫度傳感的幾個(gè)區(qū)，以確定的平均需求，或區(qū)需求最大的冷卻系統(tǒng)，將提供提高效率和控制權(quán)，只是抽樣的代表區(qū)一機(jī)組重置計(jì)劃。一補(bǔ)充的特點(diǎn)是傳感器提供區(qū)舒適度控制，可以服務(wù)的雙重功能，在沒(méi)有