The modular style CPU manual in section B contains examples of multi-unit networks on the DH-485 network. The Panelview will have to be capable of using this network.
In the project under 'Channel Configuration' - 'Chan 1 -System' tab you can set the node address. if you change it from '1' online or after changing it from '1' offline then downloading you probably will have to go offline then change the node number your DH485 driver is looking for. (I haven't done this for DH485 but having to change after downloading is true for other drivers after changing the address.)