GE DS200SLCCG2A通信卡
冗余的一种特殊混合是所谓的从属和线路冗余组合。从设备提供两个支持PNO从设备冗余的从设备，每个从设备仅提供一个PROFIBUS接口。这是一种容错解决方案。从单元一次只能在一条PROFIBUS线上进行通信，PROFIBUS线上的一个错误将导致从单元的切换。但这种解决方案的最大优点是降低了成本。因此，这是一个非常流行的解决方案。例如，它用于具有CI840的S800 I/O和具有CI920的S900 I/O。主冗余CI854A支持PROFIBUS主冗余。连接到一个控制器的两个CI854A可以配置为以冗余配置工作。冗余配置通过在Project Explorer的硬件树中配置CI854A来完成。有关冗余配置，请参阅第41页的“添加主机冗余”。
A special mixture of redundancy is the so called combined slave and line
redundancy. A slave provides two slave units supporting the PNO slave redundancy
and each slave unit only provides one PROFIBUS interface. This is a one error
tolerant solution. The slave unit will only have communication on one PROFIBUS
line at a time and a single error on the PROFIBUS line will lead to a switchover of
the slave units. But the big advantage of this solution are the reduced cost. Therefore
it is a very popular solution. It is used for example for S800 I/O with CI840 and
S900 I/O with CI920.
Master Redundancy
The CI854A supports PROFIBUS master redundancy. Two CI854A connected to
one controller can be configured to work in a redundant configuration. The
configuration for redundancy is done via configuring the CI854A in the hardware
tree of the Project Explorer. For configuration of redundancy please refer to Add
Redundancy for Master Unit on page 41.
