That's because the CTC instruction has not been active yet.
If the hours change after the 59 min then the Chour jumps to zero.
You must avoid manually crossing the 23, because it takes 1 hour before the CTC instruction becomes active.
A small programming error.
Thu Oct 12 2017, 02:51:19
(no subject)(by Ihor Nehrutsa)
to Alex
A counter increments (CTC, count up) or decrements (CTR, count
down) the associated internal count on every rising edge of the rung input condition (i.e. what the rung input condition goes from false to true).
CTC counter start from 'Start' and count up to 'Max' value.
CTC generate overfill(carry) impulse when Counter==Max.
CTR counter start from 'Start' and count down to 'Min' value.
CTR generate overfill(borrow) impulse when Counter==Min.
Try simulate ctc_osr.ld
Thu Oct 12 2017, 16:49:50, download attachment ctc_osr.ld