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Entry type: Application example Entry ID: 109482475, Entry date: 12/04/2018

Ethernet Communication (ISO on TCP) between SIMATIC S5 and SIMATIC S7-1500 Controllers

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  • Associated product(s)
In automation technology, old systems still running with SIMATIC S5 have to be upgraded – completely or step by step – to the latest version of SIMATIC S7-1500 due to the end of product lifecycle. These examples shall demonstrate how a SIMATIC S5 station communicates with a SIMATIC S7-1500 station via Industrial Ethernet (ISO on TCP).

One of the standard communication structures for systems is the star topology. A head-end station (PC or SIMATIC head-end station) communicates with several substations. These substations, however, also communicate with each other via cross-communication. In SIMATIC S5 systems, the communication of a control center/ SIMATIC S5 head-end station to its substations is often implemented by means of the FETCH/WRITE service. Cross-communication between SIMATIC S5 substations is done via the SEND/RECEIVE service.

Fig. 1

In the course of a partial migration, for example, a SIMATIC S5 station is replaced by a SIMATIC S7-1500 station. For this, the existing communication relations have to be maintained.

The example projects/scenarios in this document show the options available to establish a communication via Industrial Ethernet (ISO on TCP) between the existing SIMATIC S5 controllers and the SIMATIC S7-1500 via the available protocols and services. The figure below shows the underlying hardware setup and the communication variants of this example.

Fig. 2
This example includes 7 variants with program code and configuration instructions showing the most important communication options of the SIMATIC S7-1500 via FETCH/WRITE and Open User Communication (TSEND, TREV, TSEND_C, TRCV_C) in detail. As hardware interfaces, a CP 1430 TCP is used on the SIMATIC S5 side and a CP 1543-1 or the internal PROFINET interface of the S7-1500 CPU is used on the SIMATIC S7-1500 side.

You will be provided with master copies which can be quickly used and extended in your own migration projects. Detailed knowledge on the SIMATIC S5 is not required.

Documentation and Sample Project
  Documentation (4,9 MB)
 Registrierung notwendig  Project for S7-1500 (STEP 7 V13 SP1) (4,9 MB)
 Registrierung notwendig  Project for AG115 (STEP 5) (196,5 KB)

Further Information 
Further examples for communication with SIMATIC S5:
Sample programs for communication from SIMATIC S5 modules to SIMATIC S7 modules via Industrial Ethernet using the TCP protocol (S7-300/400)
Ethernet Communication (ISO Transport Protocol) between SIMATIC S5 and SIMATIC S7-1500 Controllers
Serial Communication between SIMATIC S5 and SIMATIC S7-1500 Controllers

Additional Keywords
ISO-on-TCP, CPU 944, NCM COM1430 TCP

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