Hi,

unfortunately it's not possible.

With the S7-1500 it is only possible with an CP1543-1 (up from firmware V2.2).
Also the S7-1500 itself needs firmware V2.8 at minimal requirement.
Futhermore, this is also only possible with TIA up from V16.

It is not possible via another CP/CM, older firmware or older version of TIA.

As an alternative you can use a router (like SCALANCE S615) to access OPC UA via another subnet.

Access to OPC UA applications

• S7-1500 CPU (except S7-1500 R/H) as of firmware version V2.8
• CP 1543-1 firmware version V2.2 or higher

regards

sancurz