First, DCS's skeleton - the system network, which is the foundation and core of DCS. 
网络对于DCS整个系统的实时性、可靠性和扩充性，起着决定性的作用，
各厂家都在这
进行了精心的设计。 As the network of the system for real-time DCS, reliability and scalability, play a decisive role, so the manufacturers have been careful in this area of design. 对于DCS的系统网络
，它
满足实时性的要求，即在确定的时间限度内完成信息的传送。 DCS system for the network, it must meet the requirements of real-time, that is completed within defined time limits of information transmission. 这里所说的“确定”的时间限度，是指在无论何种
下，信息传送都能在
时间限度内完成，而时间限度则是根据被控制过程的实时性要求确定的。 Here called "OK" time limit refers to whether the circumstances, the information transfer can be completed within this time limit, but this time limit will be under the control of the process to be determined in real-time requirements. ，衡量系统网络性能的指标并不是网络的速率，即通常所说的每秒比特数（bps），而是系统网络的实时性，即能在多长的时间内确保所需信息的传输完成。 Therefore, network performance measurement system is not the network speed indicators, known as bits per second (bps), but the network's real-time system that can ensure long time to complete the required information transmission . 系统网络还非常可靠，无论在
下，网络通信都不能中断，多数厂家的DCS均采用双总线、环形或双重星形的网络拓扑结构。 Network also have to be very reliable in any case, network communications are not interrupted, so most manufacturers of DCS were double bus, ring or dual star network topology. 
满足系统扩充性的要求，系统网络上可接入的最大节点数量应比
使用的节点数量大若干倍。 Scalability to meet the requirements of the system, the system can access the network should be the maximum number of nodes than the actual number of nodes used in a large number of times. 这样，一可以随时
新的节点，另一也可以使系统网络运行于较轻的通信负荷
，以确保系统的实时性和可靠性。 In this way, one can always add new nodes, it can also make the system run on less communication network load conditions to ensure the system's real-time and reliability. 在系统运行过程中，各个节点的上网和下网是随时
发生的，特别是操作员站，这样，网络重构会经常进行，而这种操作绝对不能影响系统的正常运行，
，系统网络应该具有很强在线网络重构功能。 Actual operation in the system process, each node of the Internet and into the net may occur at any time, especially operator station so that network reconfiguration will be conducted frequently, and this operation definitely not influence the systems up and running, so the system network should have a strong online network reconfiguration functions.
其次，这是一种
对现场I/O
并实现直接数字控制（DOS）功能的网络节点。 Secondly, it is a completely on-site I / O processing and realization of direct digital control (DOS) function in network nodes. 
一套DCS中要设置现场I/O控制站，用以分担整个系统的I/O和控制功能。 To set the general scene in a DCS I / O controllers, to share the whole system I / O and control functions. 这样既可以避免一个站点失效造成整个系统的失效，提高系统可靠性，也可以使各站点分担数据采集和控制功能，有利于提高整个系统的性能。 This will not only avoid failure due to a site caused by the failure of the system, improve system reliability, but also allows the site to share data acquisition and control functions, will help improve overall system performance. DCS的操作员站是一切与运行操作有关的人机界面（HMI-Human Machine Interface或operator interface）功能的网络节点。 DCS operator station is run operation to deal with all the human-machine interface (HMI-Human Machine Interface, or operator interface) function of network nodes.
系统网络是DCS的工程师站，它是对DCS进行离线的配置、组态工作和在线的系统监督、控制、维护的网络节点，其主要功能是提供对DCS进行组态，配置工作的工具软件（即组态软件 ），并在DCS在线运行时实时地监视DCS网络上各个节点的运行，使系统工程师可以通过工程师站及时
系统配置及
系统参数的设定，使DCS随时处在最佳的工作之下。 Network is a DCS engineer station, it is a DCS configuration offline, online system configuration work and supervision, control, maintenance of network nodes, its main function is to provide DCS configuration, configuration of tools for software (ie configuration software ) and running online in real time DCS DCS network to monitor the operation of each node so that system engineers can adjust the system configuration engineer station in a timely manner and some system parameter setting, so that at any time in most DCS under good working condition. 与集中式控制系统不同，的DCS都要求有系统组态功能，可以说，没有系统组态功能的系统就不能称其为DCS。 And centralized control systems, all of the DCS are required to have system configuration functions, can be said that no system configuration capabilities of the system would not be called DCS.<<容~源~电~子~网~版权声明：本站内容部分来源于网络，如侵犯到你的权利请及时与我们联系更正，联系QQ:316520686。
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