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Entry type: Application example Entry ID: 23809864, Entry date: 11/14/2006

Communication between SIMATIC S7-CPUs on PROFIBUS and Allen-Bradley Controllers via SST PROFIBUS Scanner

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The increasing networking of different systems also increases the necessity for SIMATIC products to communicate with devices of third-party suppliers. In this connection, Allen-Bradley or Rockwell products, which have a high market penetration especially in the USA, are of particular interest.

This application presents a solution by means of which the direct data exchange between an S7-300 and an Allen-Bradley "ControlLogix" CPU can be managed.

The solution consists of the connection of a ControlLogix CPU to an existing PROFIBUS network with the aid of a "PROFIBUS scanner".

This scanner is a plug-in card of a third-party supplier (SST Woodhead), which is installed in the rack of the ControlLogix. The scanner presents itself as an I/O module to the ControlLogix; on the PROFIBUS side, the scanner acts as a master polling the slaves. In this case, there is a direct data exchange between the CPUs. The S7-300 CPU here acts as an intelligent slave which exchanges data with the scanner. The data are transferred to and fro between the process images of the two CPUs.

The advantage of this method is that the application is simple and sturdy and that there are no restrictions with regard to the network via which the ControlLogix CPU is connected to its I/O devices.


Content of Downloads


Documentation (German)  23809864_AB_ProfibusScanner_DOKU_V10_d.pdf ( 2089 KB )
Documentation (English)  23809864_AB_ProfibusScanner_DOKU_V10_e.pdf ( 2159 KB )
S7 Configuration, Configurations for Allen-Bradley Configuration Tools RSLogix 5000 and SST Profibus Configuration Tool
23809864_AllenBradley_S7300_PB_Scanner_CODE_v10.zip ( 416 KB )





10/2006 first edition


Additional Information



Communication between SIMATIC S7 and Allen-Bradley ControlLogix CPUs via Ethernet: Use of "Echochange" gateways 23901499
Connection between PROFIBUS Subnets and DeviceNet by AnyBus-X-Gateways 23902276


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