Posted 19 Mar 2015 Hello everybody, I have a problem connecting CS1G-H CPU42 with CS1W-PRM21. Prm21 is inserted in slot 9, and i have previously made connection to prm21. After downloading configuration to prm21 i cant connect to prm21 anymore (connection to plc is working fine). The cx-configurator says CS1W-PRM21 PROFIBUS DP-V1 Master Communication Failure with UnitERH is on (red), BF is flashing red, RUN is on (green), PRM is on (green) and BST is flashing green. How can i restore comunication with the cs1w-prm21 to diagnose the problem? After some examination the problem is (probably) that i have configured prm21 to write in the adresses of CIO3000 to CIO3400. That is interfiering with other address. Is there any way to force the output of the prm21 off, or make device go in offline mode.At the power on of the prm21, i can test the connection via cx-configurator and is working and after 2 seconds the prm21 goes to stop mode and begin writing to address of the sysmac bus area. I am thinking if i can stop prm21 from writing to that area i will be able to connect and load default configuration.is that any way to stop the prm21 from automatic start? or is there a way to reset prm21 to factory settings? best regards Share this post Link to post Share on other sites
Posted 19 Mar 2015 I have deleted routing table in the plc via cx-net (i have made backup of it) and erh error of the prm21 has turned off. I still cannot connect to the prm21. Share this post Link to post Share on other sites
Posted 25 Mar 2015 The problem was solved after some assistence from omron turkey. the solution: short circuit a and b lines from profibus to make hardware error and then the unit will go into offline mode, thus can communicate with the plc (or pc) Share this post Link to post Share on other sites
Posted 10 Sep 2015 this is excellent, this just solve my problem which was similar to yours. thanx omron turkey! Share this post Link to post Share on other sites