Hello everyone, I am currently facing difficulties with the S7-1200 PLCs we are utilizing in responding to remote requests when using port forwarding on the cellular modems provided by my client. The PLC is able to respond when a VPN is used, but the client has opted against it, presenting me with three possible solutions. Firstly, I need to find a way for these units to communicate via Modbus TCP through a port forwarded on the modem. Alternatively, adding a second modem and utilizing IP passthrough could be a viable option. Lastly, transferring data to another device and reading it there is also a possibility. I am particularly interested in pursuing the first option. Siemens technical support has mentioned that they have successfully tested this method, albeit without offering any specific guidance on the setup process. The PLC model in use is a 1214 on version 17, with the CPU running on v4.6.1 firmware and the project configured with v4.5. The cellular modem is a Sierra Wireless device. If anyone has any suggestions or ideas to offer, I would greatly appreciate it. Thank you.
We have made sure to address the security risks associated with these settings, and the users are informed about them. After examining my files, I noticed a remote port setting within the modbus block set to 0 by default. Should this be changed to a more secure option such as 502? Additionally, I am having difficulty accessing the units remotely through TIA Portal. It would be beneficial to enable this feature. At the moment, both ports 502 and 102 are forwarded on the modem.
Have you configured your hardware to connect to the IP address of your cellular modem? Keep the remote port at 0, as that is the correct setting. I have successfully accomplished the same task multiple times in the past, confirming that going online with TIA and using modbus TCP is indeed achievable.
Thank you for your feedback! I have configured the gateway to the private IP address of the modem. While the PLC responds when pinged through the modem's management software on the private side, I am unable to get a response to remote requests. Port forwarding for ports 102 and 502 has been correctly set up, as I am able to remotely view an HMI on the same modem. Could this be a modem issue or is there a missing setting? I am testing functionality using TIA and seeking access to devices via my wireless connection.
Are you wondering if the PLC acts as a Modbus TCP server or client? Understanding the direction of communication is crucial for seamless operations.
The individual seeking services is a valuable client.
✅ Work Order Management
✅ Asset Tracking
✅ Preventive Maintenance
✅ Inspection Report
We have received your information. We will share Schedule Demo details on your Mail Id.
Answer: Answer: Troubleshooting S7-1200 PLC port forwarding issues for remote communication can involve ensuring proper configuration of port forwarding on the cellular modem, checking compatibility with Modbus TCP communication, and seeking guidance from Siemens technical support if needed.
Answer: Answer: If VPN is not an option for remote communication with S7-1200 PLCs, possible solutions include setting up Modbus TCP communication through a port forwarded on the modem, utilizing IP passthrough with a second modem, or transferring data to another device for reading.
Answer: Answer: Enabling S7-1200 PLCs to communicate via Modbus TCP through a port forwarded on the cellular modem may involve configuring the port forwarding settings on the modem, ensuring compatibility with the PLC model and firmware version, and seeking specific guidance from Siemens technical support or experienced professionals.
Answer: Answer: When setting up remote communication with S7-1200 PLCs using a Sierra Wireless cellular modem, it
Join hundreds of satisfied customers who have transformed their maintenance processes.
Sign up today and start optimizing your workflow.