Siemens OPC UA

For communication with Siemens S7 PLCs, DataTalk uses the OPC UA protocol via the PLC’s integrated OPC UA server. This driver provides high security, interoperability, and reliability — the recommended option for Siemens industrial data exchange.

Requirements

Before establishing the connection, ensure:

• Your PLC supports OPC UA Server functionality — S7-1200 and S7-1500 series with firmware that includes OPC UA support
• The OPC UA Server feature is licensed and enabled on the PLC
• The PLC is reachable from the DataTalk server over the network (check IP, firewall, and VLAN settings)

Enabling OPC UA in TIA Portal

1. Open TIA Portal and load your PLC project.
2. In the Project Tree, navigate to: Devices → [Your PLC] → Properties → General → OPC UA
3. Enable “Activate OPC UA Server”.
4. Configure:
   • Endpoint URL — e.g. opc.tcp://<PLC_IP>:4840
   • Security Policy — choose Basic256Sha256 with Sign & Encrypt
   • User Authentication — set username/password or certificate-based auth
5. Under OPC UA → Access Rights, add the data blocks, inputs/outputs, or variables to expose.
6. Download the configuration to the PLC and restart if required.

Configuring the DataTalk connection

1. Create a new Siemens OPC UA connection in DataTalk.
2. Enter the PLC’s endpoint URL (e.g. opc.tcp://192.168.0.10:4840).
3. Import or trust the PLC’s server certificate if certificate validation is enabled.
4. Provide authentication — username/password or client certificate/private key.
5. Test the connection — DataTalk lists available OPC UA nodes from the PLC.
6. Map the desired nodes to DataTalk tags for use in dashboards, alarms, or data logging.

Security notes

Always use Sign & Encrypt mode in production. Use a unique certificate per client connection. Keep PLC firmware and DataTalk software updated to maintain security compliance.