Hello, fellow engineers. I'm experiencing communication issues between PLC (S7-1214C AC/DC/RLY, FW V4.4) and HMI (KTP700 Basic, FW V15.1). Both are on the same subnet mask: 255.255.255.0, with IP addresses for PLC and HMI being 192.168.0.1 and 192.168.0.2, respectively (my PC is 192.168.0.5). All devices are connected through a HUB/SWITCH (in Network connection, the connection appears as green lines, and there's a window showing HMI_connection1). I programmed using TIA Portal V19, and I can ping both devices normally. Additionally, I've set the PLC to full access, and the HMI's date/time is synchronized with the PLC (including time zone/time shift). I've configured Set PG/PC interface to S7ONLINE (STEP 7) -> Realtek PCle GbE Family Controller.TCP.Auto1 <Active>. I wrote a simple test program in OB1 for Start-Stop a lamp using data in the Data block (uncheck optimization) and %Q0.0 (data block information is linked with the HMI tag as an absolute tag). Then I assigned tags to various elements on the HMI screen (2x push button & 1x circle). My problem is that when I start runtime or download the program to HMI, a pop-up shows "140001: Connection disconnected," and when I press the Start or Stop button, a pop-up shows "190011: The tag xxx: value could not be written to the PLC," even though the PLC can execute commands when there's a tag value modification (force table).

I hope everyone can help resolve this issue.

Sincere,

LPK

For a HMI to communicate with the PLC, the Profinet name has to match on the device, to what you have configured in the PLC hardware config. As it's a Basic panel, you need to set the device name manually in the HMI.

Also make sure that there is a HMI communication link in the HW configuration.