I configured longer operation times for my desktop session by the means of the KDE system settings.
Now I am wondering why this system is still put to sleep in shorter time intervals than what I would expect so far. :\
Where should I take another look for corresponding adjustments?
This is too vague :(. Exact description of which parts of System Settings used (I count seven rows of up to seven items, and each of them has from one to four or more sub-items) and which parameters you changed from what to what.