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智能定位器调节阀通过HART通讯实现运行监控发布时间：2021-08-03T06:41:09.914Z 来源：《电力设备》2021年第5期作者：刘卓[导读] 可以大大提高维修效率，减少维修及停机时间，降低维修成本。
（中国石油哈尔滨石化分公司仪电车间）摘要：智能定位器调节阀在线监测、诊断、组态、校验等，实行一体化管理方案，对调节阀的实际状况进行实时性监控及处理，能够提供准确有效的数据，编制有针对性的维修策略。
以Honeywell的PKS系统模拟量输出AO卡为基础，通过HART通讯，采集智能定位器实时运行数据，实现调节阀在线监测与诊断，达到调节阀预知维修的目的。
中关键词：预知维修；智能定位器；调节阀；HART通讯；模拟量输出AO卡；阀门监控前言工业4.0时代下，利用大数据以及智能仪表的数据分析而推出的预知性维修，已经成为发展趋势。
智能定位器调节阀在线监测、诊断、组态、校验等，实行一体化管理方案，对调节阀的实际状况进行实时性监控及处理，能够提供准确有效的数据，编制有针对性的维修策略，使调节阀的维护更加方便可靠。
可以大大提高维修效率，减少维修及停机时间，降低维修成本。
一、调节阀专业维修存在的短板现阶段，调节阀专业维修工作主要以“事后维修”为主，“预防维修”为辅，不能有效开展预知维修工作。
主要体现在以下方面：1.机械式定位器调节阀，通过DCS系统完成基本的调节控制。
缺乏对调节阀本体的实时监测功能，缺乏对调节阀运行状况变化的分析与预测功能。
对于调节阀卡涩、动作偏差、运行缓慢故障等不能进行预警。
2.智能定位器调节阀，虽然支持HART协议，但未能实现与DCS系统的实时通讯，缺乏对调节阀本体的实时监测功能。
在日常工作中，维护人员只能以“点对点”模式进行维护。
利用手操器，在现场对单台智能定位器进行参数整定、自动校验等操作，效率低下。
而且，智能定位器的自诊断、在线组态、在线校验等功能，未能与DCS系统相互融合，未能充分发挥智能定位器的作用，DCS系统缺乏对整套装置智能定位器集中监测管理的功能。
Products Solutions ServicesTI00027S/04/EN/17.1871393078Technical InformationWirelessHART Fieldgate SWG70Intelligent WirelessHART gatewaywith Ethernet and RS-485 interfaceApplicationFieldgate SWG70 is a gateway for WirelessHARTnetworks. It enables WirelessHART field devices to communi-cate with each other and manages network security and connec-tivity. Fieldgate converts and saves the wireless field device data to a format that is compatible with other systems.It has Ethernet and serial interfaces to connect to host applica-tions such as SCADA tools.Your benefits•Easy commissioning and diagnosis of a self-organized WirelessHART network•Seamless integration of field device information into higher-order system applications using standardized protocols such as MODBUS, EtherNet/IP, HART-IP or OPC•Wireless configuration and management of smart field devices in a facility using FieldCare•Flexible use of Fieldgate in hazardous areas of a facilityWirelessHART Fieldgate SWG702Function and system designWirelessHART WirelessHART adds wireless capabilities to the HART protocol, while guaranteeing compatibility withexisting HART devices, commands and tools.A WirelessHART network comprises:•WirelessHART field devices•Wired field devices with a connected WirelessHART Adapter•FieldgateThe WirelessHART protocol may not be used to replace the wiring in the case of safety applicationswith a control function.WirelessHART Fieldgate SWG70The WirelessHART Fieldgate SWG70 acts as an interface between the WirelessHART network and a system that has an Ethernet or RS-485 connection.The WirelessHART Fieldgate SWG70 supports the following functions:•Wireless network configuration and management•Acquisition of data from the field devices and presentation to connected systems •MODBUS, HART, HART-IP, OPC and EtherNet/IP support for system integration •Configuration of network, Fieldgate and field devices via Web interface or FDT/DTM.Fieldgate is designed for installation in hazardous areas Zone 2. You can mount the antenna directly on the Fieldgate or remotely depending on the requirements of the application.System design The WirelessHART Fieldgate stores information received from the WirelessHART Adapter SWA70or other WirelessHART field devices in a buffer which can be accessed by a host application via anEthernet or RS-485 connection. The figure shows a Fieldgate operating in a typical meshed Wire-lessHART network architecture.1Host application 2Ethernet 3WirelessHART Fieldgate4Field devices with WirelessHARTWirelessHART Fieldgate SWG703InputCommunication interface WirelessHART communication interface (IEC 62591)Transmission rate Nominal 250 kbits/s Transmission range 2.4 GHz (ISM band)RangeUp to 250 m outdoors, up to 50 m indoorsTransmission power Configurable to 0 dBm or 10 dBm, for adapting to national regulations Input variables•Process variables according to HART standard are sent to the network by the field devices in the burst mode.•Up to 250 WirelessHART-based devices can be connected.OutputOverview of versions and protocolsAll Fieldgate SWG70 versions feature an Ethernet interface and a serial interface. Depending on the device version, this interface can support different protocols.1)For OPC, there is an OPC DA server. The software is included in the scope of delivery and must be installed ona Windows PC.Ethernet (via MODBUS-TCP or OPC)Communication interfaces Configurable for HART-IP and MODBUS-TCP communication Protocols HART-IP, MODBUS-TCP and also OPC serverPhysical layer Ethernet 10 BASE-T/100 BASE-TX, complete galvanic isolation Transmission rate 100 Mbit/s (max. cable length 100 m at 25 °C ambient temperature)Type of protection NoneMaximum bus length 100 m (110 yds) depending upon cableConnection facilities•7-port terminal block•Screw terminals: 0.2 mm 2 to 4 mm 2 for solid wire and 0.2 mm 2 to 2.5 mm 2 for stranded wiresFieldgateSWG70 version Interface Protocol MODBUS EtherNet/IP HART-IP AMS SWG70-xx-1ModbusEthernet X –X X Serial (RS-485)X –X –SWG70-xx-2MODBUS + OPC 1)Ethernet X –X X Serial (RS-485)X –X –SWG70-xx-3EtherNet/IPEthernet –X X X Serial (RS-485)––X–WirelessHART Fieldgate SWG704Ethernet (via EtherNet/IP)Communication interfaces Configurable for HART-IP and EtherNet/IP communicationProtocols HART-IP and EtherNet/IPPhysical layer Ethernet 10 BASE-T/100 BASE-TX, complete galvanic isolationTransmission rate100 Mbit/s (max. cable length 100 m at 25 °C ambient temperature)Type of protection NoneMaximum bus length100 m (110 yds) depending upon cableConnection facilities M12 connectorRS-485 serial interfaceCommunication interfaces Configurable for HART Version 7.0 or MODBUS RTU communicationTransmission rate Hardware or software configurable between 1200 Bit/s to 115200 Bit/sType of protection NoneGalvanic isolation Fully isolated from all other circuitsMaximum bus length1200 m (1230 yds), depending upon cable and transmission rateTerminal resistor Integrated, settable by hardware (DIP-switch) or softwareConnection facilities•Two 3-port terminal blocks, allowing series connection of several Fieldgates•Screw terminals: 0.2 mm2 to 4 mm2 for solid wire and 0.2 mm2 to 2.5 mm2 for stranded wiresPower supplyPower supply20 VDC to 30 VDC SELV / PELVPower<5 WConnection facilities•Two 2-port terminal blocks, 2nd port for redundant power supply•Screw terminals: 0.2 mm2 to 4 mm2 for solid wire, 0.2 mm2 to 2.5 mm2 for stranded wiresWirelessHART Fieldgate SWG705Operating conditionsApplication rangeThe Fieldgate SWG70 serves as a gateway for WirelessHART networks.The WirelessHART protocol may not be used to replace the wiring in the case of safety applications with a control function.Installation conditionsInstallation instructionsEnvironmentAmbient temperature range –20°C to +60°C (–4°F to 140°F)Storage temperature –40°C to +85°C (–40°F to +185°F)Relative humidity 5% to 95%, non-condensingVibration resistance EN 60068-2-6: 10 Hz ≤ f ≤ 150 Hz/1g Shock resistance EN 60068-2-27: 15 g, 11 msElectromagnetic compatibilityThe WirelessHART Fieldgate meets EU Directive 2004/108/EC "Electromagnetic compatibility"•EN 61326:– Interference immunity: EN 61326-1, 2006, Industry – Interference emission: EN 61326-1, 2006, Class ALocation:Avoid mounting the WirelessHART Fieldgate near a pipe or high-voltage equipment wherever possible.Where possible, the WirelessHART Fieldgate should be in radio contact with at least 20% of all wireless field devices or adapters.Under typical conditions, the maximum spacing is 250m outdoors and 50m indoors.Installation: A remote antenna can be mounted outside a cabinet.Orientation:With vertical antenna.Protection against lightning:If there is a risk of lightning, install suitable antenna accessories. See “Accessories” on page 7.Connect the protective ground to the protective ground connection of the Fieldgate housing. The minimum cross-section of the protective ground is 2.5mm 2.Hazardous area:Fieldgates with the appropriate certification (see ordering information) can be mounted in Zone 2.The housing cover can be removed in Zone 2 to view the LEDs. It is not permitted to operate any switches in an explosive atmosphere.WirelessHART Fieldgate SWG706Mechanical ConstructionOverall dimensionsWeight Approx. 1.6 kgHousing•Material: Painted aluminum•Color: Light gray, RAL 7035Degree of protection IP 66 / IP 67Antenna•Omnidirectional dipole antenna•Remote antennas: See “Accessories” on page7.OperationConfiguration•Web browser via Ethernet•FieldCare via Ethernet (HART IP CommDTM) or RS-485 (serial CommDTM)Operating elements•2x Pushbuttons within housing for selecting operating mode during local configuration•5x LEDs within housing for indicating current operating mode during local configuration•1x 8-position DIP switch for HART device address (1 to 4),baudrate of RS485 interface (5 to 6), terminating resistor (7) and security mode (8)hardware settings can be overwritten by software settings.IP address•Configurable via Web browser or DTM, default 192.168.1.1•The EtherNet/IP version of Fieldgate uses DHCP to assign the IP addressConfigurable functions•Wireless network•HART, MODBUS and Ethernet communication interfacesWirelessHART Fieldgate SWG707Diagnosis•Display of wireless field device list with process values of selected field device•Display of wireless field device list with burst message identification of selected field device •Network monitoring of wireless communication events •Diagnostic functionAccessoriesAntenna accessoriesNote the following when selecting accessories for the antenna:•The Ex approval for Fieldgate SWG70 is only valid for the 2dBi antenna supplied.•The antenna must comply with the rules for the usage of 2.4GHz equipment that apply in the country of installation. In case of doubt, please contact a regional expert for radio approvals.•The gain is calculated from the difference in the antenna gain and the losses of the individual components such as the cables and surge arrester. The gain may not exceed the 2dBi limit.•The WirelessHART range of the Fieldgate SWG70 depends on the coaxial cable used (attenuation) between the Fieldgate and the antenna.Fig.1: Calculating the maximum gain of a remote antenna1Antenna2Coaxial adapter3RF coaxial cable with connectors4Surge arrester, λ/4, without mechanical fixing 5Fieldgate SWG70Order No.Description Fig. No.Antenna gain (Gain)Loss (attenuation)71131503Remote panel antenna Kit incl. coaxial adapter and mounting bracket 1 and 28.5 dBi –71131502Remote dipole antenna Kit incl. coaxial adapter 1 and 2 6.0 dBi –71131504Remote cabinet antenna Kit incl. coaxial adapter 1 and 2 6.0 dBi –71131509Coaxial cable 2.5 m 3–0.5 dB 71131508Coaxial cable 5 m 3– 1.1 dB 71131507Coaxial cable 10 m 3– 2.1 dB 71131506Coaxial cable 15 m3– 3.2 dB 71131505Surge arrester (protection against lightning) 4–0.2 dBWirelessHART Fieldgate SWG708Ordering informationProduct structureDetailed information about the product structure is available:•On the Endress+Hauser website: /SWG70•From your Endress+Hauser Sales Center: Accessories•Remote antennas and antenna accessories: See “Accessories” on page 7.•Additional accessories on requestDocumentationWirelessHART Fieldgate SWG70Certificates and ApprovalsCE MarkThe WirelessHART Fieldgate SWG70 meets the legal requirements of the relevant EU directives. Endress+Hauser confirms successful testing of the WirelessHART Fieldgate SWG70 by affixing to it the CE mark.Hazardous area approvalsSee the "Documentation" section.IT securityEthernet interfaceThe Fieldgate SWG70 is equipped with security mechanisms to protect it against any inadvertent changes to the device settings. Additional IT security measures in line with operators' security stan-dards and designed to provide additional protection for the device and device data transfer must be implemented by the operators themselves.If network firewalls are used, the following TCP/IP ports must be specifically open:❑WirelessHART Fieldgate SWG70Operating Instructions BA00064S/04/en ❑Wireless Adapter and FieldgateCompetence Brochure CP00013S/04/en ❑WirelessHART Fieldgate SWG70Safety Instructions ATEX /IECEx XA00001S/04/a3❑WirelessHART Adapter SWA70Operating Instructions BA00061S/04/en❑WirelessHART-Fieldgate SWG70Control Drawing XA01565S/04/enPort Service UseAccess to67/UDP,68/UDP Client IP address assignment via DHCP Fieldgate IP address (write)53/UDP,53/TCP Client DNS: name resolution 443/TCPServerHTTPS over SSL: Web server – Fieldgate configurationFieldgate (read and write),AES-128-bit-SSL-encrypted, additionally password-protected 502/TCP Server System integration via MODBUS/TCPProcess values (read only)5094/TCP 5094/UDP Server Operation via DTM and OPC server system integration via HART-IP Fieldgate and WirelessHART devices (read and write)33333Server AMS system integrationFieldgate and WirelessHART devices(read and write)44818/TCP,2222/UDPServerSystem integration via EtherNet/IPFieldgate and WirelessHART devices (read and write)WirelessHART Fieldgate SWG709WirelessHART interface Security is implemented with end-to-end sessions utilizing industry standard AES-128-bit encryption For more information see: /hcp/tech/wihart/wihart_security.htmlRadio approvalsTelecommunication approvals•Europe: Radio Equipment Directive•USA and Canada: FCC Part 15.247 for wireless applications in the 2.4 GHz frequency band •Brazil: ANATEL UL-BR 15.0983 (EAN Number: 7898994191414) •China: CMIIT ID (SRRC)•Japan: Ministry of internal affairs and communication •Mexico: COFETEL RCEPNSW12-0651•Other national certificates are available on request.Additional national guidelines to be observed:Europe This device complies with the requirements of the EC Radio Equipment Directive 2014/53/EU.•ETSI EN 300 328: V1.8.1:2012USA and Canada This device complies with part 15 of the FCC Rules.This device complies with CFR 47, Part 15 of the FCC Rules. The operation of this device is subject to the following two conditions:(1) This device may not cause harmful interference, and (2) this device must accept any interference received, including interference that may cause undesired operation.Country GuidelineBulgaria General authorization required for outdoor use and public service Italy If used outside of own premises, general authorization is required.Norway May be restricted in the geographical area within a 20 km radius from the center of Ny-Alesund.Romania Use on a secondary basis. Individual license requiredLatviaThe outdoor usage of the 2.4 GHz band requires an authorization from the Electronic Communications Office.WirelessHART Fieldgate SWG7010BrazilANATEL UL-BR 15.0983 (EAN Number: 7898994191414)“Este produto está homologado pela ANATEL, de acordo com os procedimentos regulamentados pela Resolução 242/2000, e atende aos requisitos técnicos aplicados.”Para maiores informações, consulte o site da ANATEL .brChineseThis device has been granted a type approval by the SRRC (State Radio Regulatory Commission of P. R. China): CMIIT ID 2011DJ5309JapaneseThis device has been granted a designation number by the Japanese Ministry of Internal Affairs andCommunications according to the Ordinance concerning Technical Regulations Conformity Certifica-tion etc. of Specified Radio Equipment ( )•Article 2 clause 1 item 19•Approval n°: 202WW09117712This device should not be modified (otherwise the granted designation number will be invalid).MexicoCOFETEL Approval No.: RCPENSW12-0651La operación de este equipo está sujeta a las siguientes dos condiciones:(1) es posible que este equipo o dispositivo no cause interferencia perjudicial y (2) este equipo o dis-positivo debe aceptar cualquier interferencia, incluyendo la que pueda causar su operación no deseada.WirelessHART Fieldgate SWG7011WirelessHART Fieldgate SWG70 。
H A RT技术指南12smar在智能设备系统中，H A RT 通讯协议的好处介绍H A RT 现场通讯协议是工业界广泛认可的标准，在4-20mA 智能设备的基础上增加了数字通讯能力。
该技术的普及使用非常迅速，目前，事实上所有主要设备供应商都H A RT 提供协议产品。
H A RT 协议是唯一向后兼容的智能仪表解决方案，在一条电缆上可以同时传递4-20mA 模拟信号和数字信号。
H A RT 在提供现场总线的好处时，保留对现有4-20mA 系统的兼容性。
本文进行H A RT 协议的概要介绍及该项技术的主要优势。
具统计，每台设备在安装调试初期节约成本 $300-500，并且在每年节约维护和运行成本 $100-200。
模拟 + 数字通讯许多年以来，过程自动化设备使用的现场通讯标准是毫安模拟电流信号。
在大多数应用中，正比于所代表的过程参数，毫安信号在4-20mA 之间变动。
事实上，所有已安装的工厂仪表系统都使用这一国际标准同过程变量信息通讯。
H A RT 现场通讯协议扩展了4-20mA 标准，在智能测量和控制仪表的基础上提高了通讯能力。
作为过程控制演变的重要一步，HART 协议促进了过程仪表功能的大幅度革命。
该技术增强的通讯特性反应在其协议名称上，HART ”H i g h w a y A d d r e s s a b l e R e m o t e T r a n s d u c e r ”（高速远程可寻址转换器）。
H A RT 协议智能仪表在不干扰4-20mA 模拟信号的同时允许双向数字通讯。
4-20mA 模拟和 HART 数字通讯信号能在一条线对上同时传递。
主要变量和控制信号信息由4-20mA 传送 (如果需要)，而另外的测量、过程参数、设备组态、校准及诊断信息在同一线对、同一时刻通过HART 协议访问。
与其他过程仪表“开放”的数字通讯技术不同的是，HART 兼容现有系统。
H A RT 技术H A RT 协议使用 Bell202 频移键控(FSK) 标准，在4-20mA 基础上叠加低电平的数字信号。
竭诚为您提供优质文档/双击可除hart,协议,如何实现模拟信号与数字信号的混合传输篇一：haRt和4-20ma仪表输出信号为什么选择4-20ma电流的原因仪表输出信号为什么选择4-20ma电流的原因？变送器的传统输出直流电信号有0-5V、0-10V、1-5V、0-20ma、4-20ma 等，目前最广泛采用的是用4~20ma电流来传输模拟量。
工业上最广泛采用的是用4~20ma电流来传输模拟量。
采用电流信号的原因是不容易受干扰。
并且电流源内阻无穷大，导线电阻串联在回路中不影响精度，在普通双绞线上可以传输数百米。
上限取20ma是因为防爆的要求：20ma的电流通断引起的火花能量不足以引燃瓦斯。
下限没有取0ma的原因是为了能检测断线：正常工作时不会低于4ma，当传输线因故障断路，环路电流降为0。
常取2ma作为断线报警值。
电流型变送器将物理量转换成4~20ma电流输出，必然要有外电源为其供电。
最典型的是变送器需要两根电源线，加上两根电流输出线，总共要接4根线，称之为四线制变送器。
当然，电流输出可以与电源公用一根线（公用Vcc或者gnd），可节省一根线，称之为三线制变送器。
其实大家可能注意到，4-20ma电流本身就可以为变送器供电，如图1c所示。
变送器在电路中相当于一个特殊的负载，特殊之处在于变送器的耗电电流在4~20ma之间根据传感器输出而变化。
显示仪表只需要串在电路中即可。
这种变送器只需外接2根线，因而被称为两线制变送器。
工业电流环标准下限为4ma，因此只要在量程范围内，变送器至少有4ma供电。
这使得两线制传感器的设计成为可能。
在工业应用中，测量点一般在现场，而显示设备或者控制设备一般都在控制室或控制柜上。
两者之间距离可能数十至数百米。
按一百米距离计算，省去2根导线意味着成本降低近百元！因此在实际使用中两线制传感器得到越来越多的应用。
仪表输出信号为什么选择4-20ma电流的原因：远传信号用电流源优于电压源的原因：因为现场与控制室之间的距离较远，连接电线的电阻较大时，如果用电压源信号远传，由于电线电阻与接收仪表输入电阻的分压，将产生较大的误差，而用恒电流源信号作为远传，只要传送回路不出现分支，回路中的电流就不会随电线长短而改变，从而保证了传送的精度。
HART技术一、HART概述目前在世界各地所安装的大多数智能现场设备均具有HART功能。
但是，初次接触自动化领域的一些朋友可能需要重温这项强有力的技术。
简而言之，HART（高速可寻址远程传感器）协议是在智能设备与控制或监测系统之间的模拟线缆上发送和接收数字信息的全球标准。
更具体地说，HART是一个双向通信协议，提供智能现场仪表和主机系统之间的数据访问。
主机可以是任何软件应用程序，从技术人员的手持设备或笔记本电脑，到工厂中使用任何控制平台的过程控制、资产管理、安全或其他系统。
为现有工厂提供数字化升级HART技术为下述这些工厂的运营者提供了一项可靠的、长远的解决方案，他们努力寻求发挥拥有数字通信功能的智能设备的优势–该数字通信功能在大多数安装设备中都已存在。
然而在许多情况下，大多数应用程序无法为其现有的自动化系统加装能够接受HART协议所提供数字数据的系统。
由于目前运行的大多数自动化网络，均基于传统的4 - 20mA模拟线路，从而HART技术便可以发挥重要的作用，因为数字信息是与4 - 20mA信号同步通信的。
没有它，就不会有数字通信。
重要的、数字化作用当用于智能设备的调试投产和校准以及连续在线诊断时，HART技术易于使用且非常可靠。
有几个原因使得我们需要拥有可与智能设备通信的主机。
包括：∙设备的配置或重新配置∙设备诊断∙设备故障排除∙读取设备所提供的额外测量值∙设备状况和状态∙其它原因：使用HART技术拥有诸多好处，而且不断有更多的用户在他们的项目中报告其所带来的好处。
欲了解更多信息，请访问成功故事利用这些优势的成功经验解释了为什么HART技术能够成为所有通信协议中最大的协议，并安装于世界各地3千多万台设备之中。
如果您曾经使用座机电话，通过观察来电显示来了解打电话的是谁，您已经知道了HART协议所做的一半工作，即它告诉“谁”在打电话。
在工业自动化网络中，这个“谁”便是基于微处理器的智能现场设备。
除了让这种智能现场设备“给家打电话”之外，HART通信还让主机系统向智能仪表发送数据。
hart协议采样率-概述说明以及解释1.引言1.1 概述概述部分的内容旨在简要介绍文章的主题和背景，以及探讨的问题和目的。
对于这篇文章，概述部分可以采用以下内容：概述Hart协议是一种常用于工业自动化领域的通信协议，它允许数字和模拟设备与监测和控制系统进行双向通信。
这种协议在工业过程控制领域有着广泛的应用，因为它可以实现高效、可靠的数据传输，并方便诊断和维护工业设备。
然而，在实际应用中，Hart协议的性能与采样率之间存在一定的关系，这也是本文要探讨的问题。
本文将介绍Hart协议的基本原理和工作机制，并重点讨论采样率对其性能的影响。
采样率是指在一定时间间隔内对信号进行采样的频率，它会直接影响到Hart协议传输的实时性和精确性。
因此，我们将探讨在不同采样率条件下，Hart协议的性能表现以及与其他因素的相互影响。
本文的目的是为读者提供关于Hart协议和采样率之间关系的理论及实际应用方面的深入了解。
通过对采样率的研究和分析，我们可以更好地理解Hart协议的特性和优势，并为实际应用中的采样率选择和系统优化提供有益的参考。
在结论部分，我们将总结Hart协议的重要性，并强调采样率对于实现高性能Hart通信的重要性。
通过本文的阅读，读者将能够更好地理解Hart协议的原理和机制，并掌握采样率与其性能之间的关系。
同时，读者也将能够应用所学知识，为工业自动化领域的Hart协议应用提供相关的技术支持和指导。
让我们开始探索Hart协议的世界吧！文章结构部分的内容可以如下所示：1.2 文章结构本文将按照以下结构来介绍Hart协议的采样率问题以及其对协议的影响和重要性。
第二章将以Hart协议的介绍为起点，深入探讨该协议的基本原理、功能和应用场景。
我们将介绍Hart协议的发展历程、工作原理以及在工业自动化中的应用示例，以帮助读者对该协议有一个全面的了解。
第二章的重点是探讨采样率对Hart协议的影响。
我们将引入采样率的概念，解释它是如何影响Hart通信的性能和可靠性的。
