How to connect to a Codesys V3 PLC using UDP/IP


When communicating with the “CODESYS V3 (Ethernet)” driver, we often suggest using TCP/IP to facilitate the connection. However, if you experience a communication delay at startup or if communication can only be resumed by unplugging and re-inserting the Ethernet cable, we may recommend using the “UDP/IP” protocol setting instead. Within this post, we demonstrate how to setup and use this setting.

Software Version:

EasyBuilder Pro
Note: Certain options within objects or windows may be placed in other locations in different versions. The example below was designed with


  1. Within the “Device settings” menu, select the “Settings…” button:

  2. Within the “Protocol” drop-down list select “V3 UDP/IP” or “V3 UDP/IP Communication Optimum”:

  3. Select the “Scan Network…” option while the PC is connected to the PLC:

  4. Choose the network adapter that is connected to the PLC:

  5. When found, select the CODESYS plc and click “OK”:

  6. EasyBuilder Pro will then assign the PLC’s “IP address”, “Port no”, and the “Source port no” to the correct settings:

  7. Click “Ok” to close the “Device settings” menu.

  8. Use the “Get Tag Info…” or “Import Tags…” button to import PLC tags: