The current implementation of the PI Interface for DNP3 does not allow the same RTU address to be used across different IP nodes. The PI Point Location3 attribute is used to specify the RTU address only. If a customer has multiple RTUs with the same address but on different IP nodes, they either have to reconfigure all of the RTUs to have different addresses, or create a new DNP3 interface instance for every IP node.

Case example:

Customer has 800 SEL-735 meters, each with a different IP address, and each with a DNP Address (RTU address) of 1. He has created an IO Group for each IP Address and one RTU in each IO Group, but there is no way to configure his PI tags to look at a particular IO Group.

Because of this limitation, his options are to reconfigure all 800 meters to use different RTU addresses, or create 800 instances of the DNP3 interface.