I'm trying to find anyone who has used the GE Modbus Concentrator for trip units before. I've got a Modbus/Modbus Plus/Ethernet network. Our Modicon Quantum PLC is set up for hot standby. Since the system can't move IP addresses from NOE to NOE after the hot standby switchover, we put in a Modbus Plus to Ethernet gateway. Now the MB+ port on the CPU is used for communications. We go thru the first bridge to get to ethernet, and then come back through a Modbus to Ethernet bridge to Modbus to talk to the GE unit and some Multilin devices. I can talk to the Multilin devices, so I know the routing addresses are correct and both bridges are working. I can get data from the GE concentrator, but not from any of the devices attached to it. Any ideas?