HIEE200130R2输出卡件

备份单元不使用冗余IP地址在网络上启动通信或响应。只有当CPU命令它成为活动单元时，它才能使用冗余IP地址。活动和备份单元都可以继续使用各自的直接IP地址，允许程序员随时连接到活动或备份PLC。PLC A PLC B冗余系统编程器远程主机（HMI、PLC等）冗余IP地址直接IP地址图2：冗余模式下的以太网操作注意：热备用（HSB）CPU和非HSB CPU支持冗余IP功能。要使用此功能，请确保为目标CPU切换启用冗余。1.4.1热备用（HSB）CPU冗余HSB系统使用冗余CPU来提供系统中PLC单元之间的协调，并确定哪个是活动单元，哪个是备用单元。HSB冗余需要专用链路来提供冗余系统中各单元之间的通信。有关HSB架构的信息，请参阅PACSystems热备用CPU冗余用户指南GFK-2308。PAC系统™ RX3i和RSTi EP TCP/IP以太网通信用户手册第1节GFK-2224Y 2019年8月简介16 1.4.2非HSB冗余非HSB系统使用RX3i CPU，这些CPU没有专门的固件来控制冗余操作。（这些CPU具有“CPE”或“CPU”名称。）在这些系统中，应用程序逻辑在充当冗余伙伴的CPU之间进行协调，并确定哪个CPU是活动单元，哪个是备份单元。图3说明了在非HSB冗余系统中使用冗余IP功能。两个非HSB CPU（指定为主CPU和辅助CPU）通过通信连接连接。每个控制器中的以太网接口配置为启用冗余IP，以便它们共享冗余IP地址。与HSB系统一样，只有活动以太网接口可以通过冗余IP地址进行通信，以产生EGD角色切换。当以太网通信切换到备份单元时，备份单元不知道先前活动单元的任何通信状态。应用程序必须包括逻辑，以检测冗余角色切换期间的通信丢失，然后重新启动通信。网络上的远程主机将冗余系统视为具有高可靠性的单个PLC；远程主机仅优先考虑活动单元。通过使用冗余IP地址，远程主机始终与活动单元通信。当冗余角色切换发生时，以前活动的PLC放弃冗余IP地址的所有权，并停止当前使用冗余IP地址进行的所有面向连接的通信。冗余系统和远程主机中的应用程序必须重新建立任何此类通信

The backup unit does not initiate communications or respond on the network using the Redundant IP address. It can only use the Redundant IP address if it is commanded by its CPU to become the active unit. Both the active and backup unit may continue to use their individual direct IP addresses, permitting programmer connection to the active or backup PLC at any time. PLC A PLC B Redundant System Programmer Remote host (HMI, PLC, etc.) Redundant IP Address Direct IP Addresses Figure 2: Ethernet Operation in Redundancy Mode Note: The Redundant IP feature is supported by Hot Standby (HSB) CPUs and non-HSB CPUs. To use this feature, be sure to toggle Enable Redundancy for the target CPU. 1.4.1 Hot Standby (HSB) CPU Redundancy An HSB system uses redundant CPUs to provide the coordination between the PLC units in the system and determine which is the active unit and which is the backup unit. HSB redundancy requires dedicated links to provide communications between the units in a redundancy system. For information about HSB architectures, refer to the PACSystems Hot Standby CPU Redundancy User’s Guide, GFK-2308. PACSystems™ RX3i and RSTi-EP TCP/IP Ethernet Communications User Manual Section 1 GFK-2224Y August 2019 Introduction 16 1.4.2 Non-HSB Redundancy Non-HSB redundancy systems use RX3i CPUs that do not have specialized firmware for controlling redundancy operations. (These CPUs have a “CPE” or “CPU” designation.) In these systems, the application logic coordinates between CPUs that act as redundant partners, and determines which CPU is the active unit and which are backup units. Figure 3 illustrates the use of the redundant IP feature in a non-HSB redundancy system. Two non-HSB CPUs (designated primary and secondary) are linked by a communications connection. An Ethernet interface in each controller is configured with Redundant IP enabled so that they share a Redundant IP address. As in an HSB system, only the active Ethernet interface can communicate through the Redundant IP address to produce EGD role-switch occurs, Ethernet communications switch to the backup unit, which has no knowledge of any communication state at the previously-active unit. The application must include logic to detect loss of communication during a redundancy role switch and to then reinitiate communication. Remote hosts on the network view redundant systems as a single PLC with high reliability; the remote host only prioritizes the active unit. By using the Redundant IP address, the remote host always communicates with the active unit. When a redundancy role switch occurs, the formerly-active PLC gives up ownership of the Redundant IP address and takes down all connection-oriented communications currently using the Redundant IP address. The applications in the redundant system and remote hosts must reestablish any such communications