I can ping the PLC over ethernet..but when I try and connect using cimplicity the connection fails and times out.
I have checked the cables and even tried cross-over connection.
Do you mean Cimplicity Machine Edition or some other Cimplicity software, as there used to be many. At one time the term Cimplicity was a proprietary term for GE software, like Proficy is today.
Are you on the same switch or network as the iFix, or plugged into a second port on the 90-70 module? What is the part number including suffix letters or version of this module?