I/A Series的最大特点是开放，在系统与MIS通讯这一层上，不论是51系列还是70系列，都可以非常方便地和工厂信息网进行通讯。Honeywell 发布TDC3000 标准系统，它增加一条UCN(Universal Control Network)网络用于取代DH网络。我们现在通常所说的TDC3000系统就是LCN UCN结构的系统。TDC3000重新对功能进行划分，在LCN上增加应用模件AM(Application Module)用于高级控制；增加PLNM（Plant Network Module）与VAX计算机的接口模件用于优化控制；将操作站与数据存储管理分开，增加了历史模件HM(History Module)；推出万能操作站US(Universal station) 在UCN上推出著名的PM系列控制器,同时引入安全系统SM(Safety Manager)用于工厂紧急安全停车。
TDC3000作为最为典型DCS系统，进一步体现了集散控制理念，主要特点有：
满足较大规模生产需要，两层控制网络架构，每条LCN可以连接10条UCN,每条UCN可连接32对冗余控制器。还可以将64 条LCN通过NG连起来。
三层控制平台
1) PMx 实现最基础的回路调节,逻辑连锁，顺序控制以及复杂回路控制。
2) AM 实现高级控制
3) VAX 实现优化控制
紧急停车系统SM的引入，实现安全生产保护。
全局数据库概念，专用的历史模件
万能操作站，同时具备操作站和工程师站能力。
TDC3000最为一套最为经典的DCS系统，满足较大规模安全生产，复杂控制和先进控制应用。被大量的应用到工业生产控制中，特别是很多石油化工大型联合生产装置。
TDC3000进一步体现了集散控制系统理念，其很多设计思想在霍尼韦尔最新的控制系统中继续得到应用。
The biggest feature of i/a series is openness. On the communication layer between the system and MIS, whether it is 51 series or 70 series, it can communicate with the factory information network very conveniently.
Honeywell released TDC3000 standard system, which adds a Ucn (universal control network) network to replace DH network. The TDC3000 system we usually call now is the system of LCN Ucn structure.
TDC3000 redistributes functions and adds Application module am (Application module) to LCN for advanced control; Add the interface module between plnm (plant network module) and VAX computer to optimize control; Separate the operation station from the data storage management, and add the history module HM (history module); The universal station us (universal station) launched the famous PM series controller on Ucn, and introduced the safety system SM (Safety Manager) for the emergency and safe shutdown of the factory.
Figure 2. TDC3000 system structure
As the most typical DCS system, TDC3000 further embodies the distributed control concept, and its main features are:
It meets the needs of large-scale production and has a two-layer control network architecture. Each LCN can be connected to 10 ucns, and each Ucn can be connected to 32 pairs of redundant controllers. 64 LCNs can also be connected through ng.
Three layer control platform
1) PMX realizes the most basic loop regulation, logic interlocking, sequence control and complex loop control.
2) Am realizes advanced control
3) VAX realizes optimal control
The introduction of emergency shutdown system SM realizes safety production protection.
Global database concept, dedicated history module
Universal operation station, with the ability of operation station and engineer station at the same time.
TDC3000 is the most classic DCS system, which can meet large-scale safety production, complex control and advanced control applications. It is widely used in industrial production control, especially in many large-scale petrochemical joint production units.
TDC3000 further embodies the concept of distributed control system, and many of its design ideas continue to be applied in Honeywell's latest control system.
