SITRAN P DSIII: use it as a manual gauge?

Edited - I realized it was a Profibus, not a HART, transmitter

If it were a HART transmitter you could wire it to the 24Vdc power supply, pipe it to whatever pressure it is you want to measure to the threaded process port, configure it for the appropriate engineering units so the displayed values make sense and it would fire up and display the pressure in the local display.

But a Profibus transmitter?   I honestly don't know.   The display and keyboard modes appear the same as for HART, but I'm not sure what influence the Profi connection has on its operation.  I suspect that the modulated Profi signal runs 'on top of' the DC current that powers the unit, but I am not sure.  Someone more familiar with Profibus PA will have to comment. 

Be prepared for people to tell you "it's broken" when the process is off, the transmitter's pressure port sees atmospheric pressure and the transmitter reports a pressure that is not zero.