Siemens SIMATIC HMI 177 Operating Instructions Manual page 86

Appendix
A.1 Connection point recognition
9. Select the system function "SetValue" from the "Calculation" group. Select the
Result
The box ID of the terminal box to which the Mobile Panel 177 is connected is transferred to
the controller.
See also
Setting the box ID at the terminal box (Page 4-7)
A-4
"External_Box-ID" tag at "Tag (output)". Select the "Internal_Box-ID" tag at "Value".
Mobile Panel 177 (WinCC flexible)
Operating Instructions (Compact), Edition 07/2005