(for example let say the I2C Dig Temp & Hum Sensor is wired to this 8 Output Module ( Modbus Address 3) I2C Termination Block to be used to get an Outside Temperature & Humidity Reading.
you would map it in sensor mapping:
hit Enter button, go into System Setup, then Setup Inputs, and you would hit enter to highlight the editing field and scroll down to change Out T to be DTH Bd3 T1 and the Out Hum to be Bd3 H1.