Daspi ATIZA 1000N Manual De Usuario página 33

When the distance between the ceiling and the bottom edge of the
track is greater than 245mm, extend the ceiling bracket.
7- Determine the highest point on the route (THP). Open the door and
measure the shortest distance between the top edge of the door and the
ceiling. This distance between the THP and the lower edge of the track
must be 5mm minimum and 65mm maximum, and the push arm must be
at a maximum angle of 30 ° (for overhead doors).
Note that if there is a doorknob on the door, this distance will be
reduced.
ATIZA 1000N