why am i not able to communicate


Thread Starter


we have two plcs and three hmi connected through ethernet and commuicating. Few days back we had to changed the old IP adresses of all nodes due to some problem. After changing IP one PLC is communicating with HMI but from other PLc i am not getting any data.

I changed IP address of PLC, HMI and in WinCC also.

How should i check and solve this problem?
For the device that is not communicating, run it through a HUB, then from the HUB to your network. Now connect a PC in to the HUB, and capture the packets with WireShark. You should be able to ascertain why this device isn't communicating (cannot open connection, not getting a response, etc).

Perhaps the new address didn't take properly, try pinging the old address/new address with a PC and crossover cable