You have to select the point in time, when the recovery-time calculation is started ("recovery time starts").
"Is it means that, when a part enter the SingleProc object, recovery time and proc time consume at the same time?"
Yes, if you select "When part enters"; then you need to define a recovery time greater than the processing time to take into account additional machining times (cleaning, clamping, loading, unloading...). The other options starts after processing or after exiting the part.
In the statistics you find the recovery time as waiting time.
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