Just some info that I recently discovered and figured was useful:
The GE 9070 cannot directly communicate with the RMC75E or RMC150E via Ethernet. One option is to use a serial to Ethernet converter. One possible one is the Lantronix UDS1100-IAP, which costs US $153 (http://www.neteon.net/prod.aspx?clvl=4&c1=1&c2=3&c3=148&p=421). It can convert Modbus/RTU to Modbus/TCP. I have tried this converter, and it works very well with a C-more HMI, so I assume it will work with the GE9070 also.
Attached is a document describing how to set up the UDS1100-IAP for communication with the RMC150E.
For converting from serial to Ethernet for other devices and protocols, here are some products:
Digi One IAP: http://www.digi.com/products/serialservers/digioneiap.jsp
AB 1761-NET-ENI: http://literature.rockwellautomation.com/idc/groups/literature/documents/pp/1761-pp004_-en-p.pdf
-Jacob
Using the Lantronix UDS1100.pdf (277 KB)