TN DA103 Troubleshooting PLC Port Communication Errors in Wonderware DAServers

Detailed Steps 

Each of the DA Servers utilizes a specific port when communicating with the PLC via TCP/IP. Below is a list of the ports used by the most common DA Servers.

Sometimes the port is blocked by a firewall or the PLC is not listening on that port. You may encounter a port refused error in the Wonderware Log Viewer. Microsoft has a utility that may be used for checking the IP address and port number of the PLC. 

The download may be found at the following link:

http://www.microsoft.com/en-us/download/details.aspx?id=17148

Run the PortQryV2.exe installer on the DA Server machine. 

Click the Yes button to accept the license agreement.

Extract the required files by clicking the Unzip button and then click the close button.

The application is installed to the PortQryV2 folder on the C drive.

Open the command prompt by typing in CMD from the start button search and press enter.

Type in portqry –n <PLC IP address> -e <port number> and the enter key.

The PortQryV2 application will return one of the following responses:

LISTENING – everything appears to be good for PLC communication.

NOT LISTENING – check to be sure you have the correct port number. A PLC configuration change may be required. This may involve a firmware update.

FILTERED – Check the network firewall to be sure the port is not blocked.