标准摘要
[中文适用范围]： 1.1 概述 现场总线应用层 (FAL) 为用户程序提供了一种访问现场总线通信环境的方法。在这方面，FAL 可视为“相应应用程序之间的窗口”。本标准为自动化环境中的应用程序和特定于 3 型现场总线的材料之间的基本时间关键和非时间关键消息传递通信提供了通用元素。术语“时间关键”用于表示存在一个时间窗口，在该时间窗口内，需要以某种定义的确定性完成一个或多个指定的操作。如果未能在时间窗口内完成指定的操作，则请求这些操作的应用程序可能会失败，从而对设备、工厂甚至人员生命造成风险。1.2 规范 本标准的主要目标是指定应用层协议的语法和行为，该协议传达 IEC 61158-5-3 中定义的应用层服务。次要目标是提供从先前存在的工业通信协议的迁移路径。正是后一个目标导致了 IEC 61158-6 系列部分协议标准化的多样性。1.3 一致性 本标准不指定单独的实现或产品，也不限制工业自动化系统中应用层实体的实现。设备与应用层服务定义标准没有一致性。相反，一致性是通过实现此应用层协议规范来实现的。 [外文原描述]： It provides user programs with a means to access the fieldbus communication environment. In this respect, the FAL can be viewed as a "window between corresponding application programs." This standard provides common elements for basic time-critical and non-time-critical messaging communications between application programs in an automation environment and material specific to Type 3 fieldbus. The term "time-critical" is used to represent the presence of a time-window, within which one or more specified actions are required to be completed with some defined level of certainty. Failure to complete specified actions within the time window risks failure of the applications requesting the actions, with attendant risk to equipment, plant and possibly human life. It includes the following significant changes from the previous edition deletion of the former Type 6 fieldbus for lack of market relevance; addition of new types of fieldbuses; partition of part 6 of the third edition into multiple parts numbered.
英文名称Industrial communication networks - Fieldbus specifications - Part 6-3: Application layer protocol specification - Type 3 elements