TRB140 connect with Siemens s71200 OPCUA

[ahmedsaude]

Hi

I am facing issues while connecting our Siemens S7-1200 PLC to the TRB140 for data transmission via TCP OPC UA to our central SCADA system over GSM 4G with an M2M Private APN:

1. I cannot find the PLC IP address in the list of connected devices—only my PC appears.
   2.How can I find the WAN IP address assigned to the PLC to search with opc server ?

I would appreciate your support in resolving these issues.

Thank you in advance.

[anon65719490]

Hello,

Thank you for reaching out.

First of all, I highly recommend updating your TRB140 device to the latest RutOS firmware version (7.16.1) or to the stable (7.15.4) version, as the current old versions lacks important fixes and improvements.

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Now, regarding your questions:

1. I cannot find the PLC IP address in the list of connected devices — only my PC appears.

• Please ensure that the PLC has the correct default gateway set, this should be the LAN IP address of the TRB140.
• Is the PLC using a static IP configuration, or is it set to receive an address via DHCP from the TRB?
• Based on your description and reviewing the ARP table, it seems that only one device (I assume your PC) is currently recognized.

This could indicate the PLC is either not connected properly, has incorrect network settings, or is on a different subnet.

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2. How can I find the WAN IP address assigned to the PLC?

If your goal is to have the PLC use the same WAN IP as the TRB140, you should consider enabling Passthrough mode on the TRB140. In this mode, the TRB will assign its WAN IP directly to the first connected LAN device (or a specific MAC address). Or, alternatively, a port forward rule could be used.

You can find more detailed information about Passthrough mode and port forwarding here:

• TRB140 WAN - Teltonika Networks Wiki
• TRB140 Firewall - Teltonika Networks Wiki

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Please check the above points and let us know how it goes.

Best regards,

[ahmedsaude]

Hello,

Thank you for your reply.

I have already configured the PLC on the same subnet, with the TRB140 IP address set as the default gateway.
However, I will double-check the configuration once again to ensure everything is correct.

Regarding passthrough mode, I will review the shared tips and test accordingly.

Many thanks for your continued support.

Best regards,