TN DA127 Using PortQry to Diagnose PLC Port Status

Description

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)

Details

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:

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

1. Run the installer to download the software.
2. Extract the files to the C (root drive) of your hard drive.
3. 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.