diff ../inc/interface.php ./interface.php

660c660,661
< 	for ($i = $rackData['height']; $i > 0; $i--)
---
> //	for ($i = $rackData['height']; $i > 0; $i--)
> 	for ($i = 1; $rackData['height'] > $i; $i++)
3570c3571
< 	for ($unit_no = $data['height']; $unit_no > 0; $unit_no--)
---
> 	for ($unit_no = 1; $unit_no < $data['height']; $unit_no++)