Problem of the connection at node red (node-red-contrib-s7) with S-1200 PLC Siemens

Industrial
1

Hi every budy
I need help!!

I had a sistem that always run without problem.
After 3 month my sistem was instable and them stop.
I have a problem of connection at node red (node-red-contrib-s7) with S-1200 PLC Siemens. Always run, but the connection status is failure

my PLC (192.168.0.104 respond to the Ping commnad

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My node red have this problem with connection at my PLC.

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I use IOT2040 to run my node red.

Thanks.
Cassio

2

Hey @Cassio, welcome to the forum!
What’s your PLC IP address? Is it in the same subnet as the device you’re trying to connect from?
Also, make sure the PLC slot number is entered correctly in s7 node, and check that your device’s firewall isn’t blocking port 102.
In TIA Portal, ensure that “Allow PUT/GET communication from remote partners” is enabled.

For more details, check out this guide:
https://flowfuse.com/blog/2025/01/integrating-siemens-s7-plcs-with-node-red-guide/#prerequisite

3

Hello, thank you.

My PLC IP address is 192.168.0.104. My IOT 2040 the IP Address is 192.168.0.110. Both Subnet Mask is 255.255.255.0
Yes, it's on the same subnet as the device I'm trying to connect from.
The node is rack 0 slot 1 on node s7 and

Yes, in TIA Portal the option "Allow PUT/GET communication from remote partners" is enabled.

The connection is run again. I think my LAN have any problem that I not see. I don´t know why my sistem stop because, I verify my LAN when the node red lost the connection with my PLC and my Internet was run. Maybe the possible problem can be the swith or other device in my LAN. I dont know, I am really lost. What are you think about?