The OT increases its's output every hour by one.
OT values are retentive allways.
It's internal timebase is 1 Min and retentive also.
Users have no access to this timebase and must create their own minute timer with a retentive counter.
See my example "OT_Min."
I prefers the second solution.
Example "Hours_Min.count".
Counters must set to retentive in the PROJECT VIEW>SYSTEM.
Observe in simulation mode with EASY-Soft after start/stop retentive values are set to 0.
This is different to real operation.
Don't forget you have to wait one hour before OT count's to 1.
Mask 1 shows actual hours/minutes.
Regard,
Julian