I hope i understand you right:
do you work with e!cockpit or Codesys Target?
If you use e!cockpit you have to assign the modbus adresses in the modbus configurator.
See the Screenshots.
i didnt know how you make this without e!cockpit...
But you can use e!cockpit Trial Version with full features. Download on Wago Homepage after registration.
Hope i could helped.
2016-08-29 13_14_34-Wago E!Cockpit - VMware Workstation.jpg2016-08-29 13_16_49-Wago E!Cockpit - VMware Workstation.jpg