TN DA127 Using PortQry to Diagnose PLC Port Status
This article covers how to use the PortQry tool to troubleshoot the status of a PLC port.
- Author: Daniel London
- Published: 06/10/2015
- Applies to: PortQry (All Versions)
When unable to communicate with a PLC, you can use PortQry to check and see if the port is open to the device.
Download PortQry Here:
- Run the installer to download the software.
- Extract the files to the C (root drive) of your hard drive.
- Once downloaded open Command Prompt.
In Command Prompt type the following to access Portqry: CD C:\PORTQRYV2
Next type the following command line to access the port you are querying:
PORTQRY -N <IP OF PLC> -E <PORT NUMBER>
Common PLC Ports:
DAS SI Direct: 102
DAS MBTCP: 502
DAS ABTCP: 2221, 2222, 2223
DAS ABCIP: 44818
The reply will be:
- LISTENING: Indicates the PLC is listening on the port number specified.
- NOT LISTENING: Indicates PortQry reached the PLC but the PLC is not listening on the port number specified. Check the PLC configuration. Also make sure the correct port is being queried.
- FILTERED: Indicates PortQry did not receive a response from the target port and the target port is being filtered. A firewall may be blocking the port. Check hardware and/or software firewall configuration.