Hi Sebastian,
I hope I understand you correctly, if i assume you want to know, where the PSP-Element you capture in IT0027 is stored.
It is stored in teh infotype as all other fields in table PA0027. If You use the first line, it's PA0027-PSP01 as in this exampel showing via transaction SE16:
Maybe you are confused, because the fields for PSP-Elements are at the very end of the table. PSP01 is the 198th field. In SE16 you may even have to click "next screen" to get there (see "previous screen" field in my screenshot.
I hope that clarifies your issue.
best wishes
Sven