173Positioning lower mark sensorPositioning lower mark sensorIntroductionThe second (or third) printing system has a mark sensor which scans thesynchronization and PTL marks on the rear side of the paper web.Note:The lower mark sensor should be positioned accordingly when the paper in use hasguide holes and use of the Data Integrity Marks is switched off.Attention:The use of data integrity marks can only be turned off if this option is activatedby Service.Data integrity marks should always be used. If you disable data integrity marks,you leave the highest possible data integrity security level.
