Hello,

I need to do the communication between two S7 400 H CPU. For this can I use S7 connection fault tolerant? or I have to use 4 S7 connections. Please help. Any details how to configure and program?

Is it possible to download both project in PLC sim and do the communication between two PLCsim instance ?

I did the communication between two PLCsim communication for S7 connection.

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Split from S7 Connection Fault-tolerant.

Hi,

About the connection, then you should see an S7 fault tolerant connection as a logical representation of a connection between two partners where there are more than one possible route to reach the partner.

You only need to define one S7 fault tolerant connection.

I recommend that you read:

SIMATIC Fault-tolerant systems S7-400H
https://support.industry.siemens.com/cs/ww/en/view/82478488

14.2 Basics and terminology of fault-tolerant communication

Michael K

Hi,

About the connection, then you should see an S7 fault tolerant connection as a logical representation of a connection between two partners where there are more than one possible route to reach the partner.

You only need to define one S7 fault tolerant connection.

I recommend that you read:

SIMATIC Fault-tolerant systems S7-400H
https://support.industry.siemens.com/cs/ww/en/view/82478488

14.2 Basics and terminology of fault-tolerant communication

 Thank you Michael K for the reply and the manual.

I have already prepared the program using BSEND and BRCV with S7 connection (not fault tolerant s7 connection). 

As shown in page 234 "User programs written for S7 connections can also be run for fault-tolerant S7 connections without program modification. Cable and connection redundancy has no effect on the user program." 

I have two questions:

1. As per the manual my program will work with the fault tolerant connection also and I don't need to do any modification in my project. Correct?

2. I have test my project with two PLCsim. The PLCsim can communicate perfectly. Is it possible to check Fault tolerant S7 Connection with two PLC sim? 

pradhan135

 Thank you Michael K for the reply and the manual.

I have already prepared the program using BSEND and BRCV with S7 connection (not fault tolerant s7 connection). 

As shown in page 234 "User programs written for S7 connections can also be run for fault-tolerant S7 connections without program modification. Cable and connection redundancy has no effect on the user program." 

I have two questions:

1. As per the manual my program will work with the fault tolerant connection also and I don't need to do any modification in my project. Correct?

- It is correct that the user program should not change by changing normal S7 connection to S7 fault tolerant. The communication block just refers to the connection and the system automatically handles the changeover.

2. I have test my project with two PLCsim. The PLCsim can communicate perfectly. Is it possible to check Fault tolerant S7 Connection with two PLC sim? 

- I know that you can run plcsim in multi instance but I am not sure if you can test the fault tolerant connection. One problem is that you cannot cut the connection (simulate a break) so it won't really be a test.

Thank you very much.

I will check on actual system.

For your information: With the S7 connection we can check the data transfer by using two PLC sim instances but some how it is not working with the fault tolerant S7 connection.

Thanks agian