I'm working on a Windows desktop application where the user deals with incoming calls by emergency devices. Because the inbound capacity is limited, the connections should be kept short, a time-out gets working if the user doesn't interact. I'm trying to make sure the limitation is understood by users without disturbing them.
Currently, I use an inverted progress bar in upright position getting a glass-half-full look.
(Text: working mode held for the 27 seconds to come)
Is there something wrong with this approach from a (professional) UX perspective?
I've also an additional question because the time-out period differs with modes and devices, ranging from 50 seconds to 9 minutes.
Should I deliver actual time-out values to the user? Or better start displaying the "regress-bar" 50 seconds before hangup?