標準號：BS EN 61158-6-7-2008
中文標準名稱：工業通訊網絡.現場總線規范.應用層協議規范.7型元件
英文標準名稱：Industrial communication networks. Fieldbus specifications. Application layer protocol specification. Type 7 elements
標準類型：L79
發布日期：2008/6/17 12:00:00
實施日期：2008/6/17 12:00:00
中國標準分類號：L79
國際標準分類號：25.040.40;35.100.70;35.160;35.240.50
引用標準：IEC 60559;IEC 61158-3-7;IEC 61158-4-7;IEC 61158-5-7;ISO/IEC 7498-1;ISO/IEC 8824;ISO/IEC 8825;ISO/IEC 9506-2;ISO/IEC 9545
適用范圍：This standard provides common elements for basic time-critical and non-time-criticalmessaging communications between application programs in an automation environment andmaterial specific to Type 7 fieldbus. The term “time-critical” is used to represent the presenceof a time-window, within which one or more specified actions are required to be completedwith some defined level of certainty. Failure to complete specified actions within the timewindow risks failure of the applications requesting the actions, with attendant risk toequipment, plant and possibly human life.This standard specifies interactions between remote applications and defines the externallyvisible behavior provided by the Type 7 fieldbus application layer in terms ofa) the formal abstract syntax defining the application layer protocol data units conveyedbetween communicating application entities;b) the transfer syntax defining encoding rules that are applied to the application layerprotocol data units;c) the application context state machine defining the application service behavior visiblebetween communicating application entities;d) the application relationship state machines defining the communication behavior visiblebetween communicating application entities.The purpose of this standard is to define the protocol provided to? define the wire-representation of the service primitives defined in IEC 61158-5-7, and? define the externally visible behavior associated with their transfer.This standard specify the protocol of the Type 7 fieldbus application layer, in conformancewith the OSI Basic Reference Model (ISO/IEC 7498) and the OSI application layer structure(ISO/IEC 9545).1.2 SpecificationsThe principal objective of this standard is to specify the syntax and behavior of the applicationlayer protocol that conveys the application layer services defined in IEC 61158-5-7.A secondary objective is to provide migration paths from previously-existing industrialcommunications protocols. It is this latter objective which gives rise to the diversity ofprotocols standardized in parts of the IEC 61158-6 series.