Connection fail to M172 for cybersecurity reason

[zsolt_zsugan_th]

Hi everyone,

After many successful connection and downloads I gave a following connection error:

When I change the port 502 to 501 I can connect to this device again.

But I need a communication port 502 to share data between this and other M172 controllers.

How can I use the port 502 again? 

I using M172 28-42 I/Os with firmware version 596.15 and Machine Expert HVAC 1.7.0.

Thanks

[ismailozinan]

Hi

You can change the PORT_ETH_PI register 15797 in the Tm172 PLC via web server or programming software Ecostruxture Machine Expert- HVAC 1.7 software with mini USB cable or if you have RS485 converter device, you can change it by accessing the device from RS485 ports. My suggestion is to use a USB cable. Even without energizing the device, you can connect via usb cable and make this change. Sincerely regards.

[zsolt_zsugan_th]

Hi  Ismailozinan,

Thank you for your answer, my problem is regarding to functionality of port 502. I can change in boot way the port number but the problem is the TCP connection on port 502 not working. So if I change the default port to 502 I cant connect to the device on TCP IP. I know I need to reenergize the PLC after every network changes.

[zsolt_zsugan_th · Accepted solution]

Hi everyone,

I found a solution for my problem the main reason was my unconsciousness. I tried to made more than 3  simultaneous TCP connections. Adding 3 additional Modbus TCP sockets to M172 ethernet interface resolves my issue.     

Sorry for my carelessness