Baumer BA Scatec10 15 - Manual (Page 21)

User manual Scatec-10 / -15 21 / 44 Baumer Electric AG
Version 2011-03 www.baumer.com Frauenfeld, Switzerland
C13: Tail edge suppression [Tail Suppr.]
Input values: 0 = stand edge suppressed if it is followed by a retro-reflective foil within the
dead time
1 = extnd edge suppressed if it is followed by a retro-reflective foil within the
output pulse delay time
Function: to define whether the area checked for tail edges extends for a dead time (0 =
stand) or for an output pulse delay time (1 = extnd).
Comments: This parameter is accessible only if menu C9 delayed output pulse (C9 = on) was
previously activated.
Delaying the output pulse (C9 = on) also automatically activates a tail edge
suppression. Parameter C13 decides which area is checked for tail edges. Tail edge
suppression does not only suppress tail edges that are sticking up, but also edges
generated by small paper scraps on the otherwise empty conveyor.
•
Tail edge suppression works only with a mounted retro-reflective foil.
•
Extended tail edge suppression works only with the front edges leading.
This configuration is sketched below.
Usually newspapers are conveyed shingled and with the folded side facing the laser
beam. As a consequence, the cut side of a copy is covered by the next copy and
exposed to the laser beam only if there is a gap in the lap stream. The cut side of
the newspaper is facing away from the laser beam, forming a tail edge and usually
not detectable by the Scatec. However, some of these cut pages might be bent up.
In the case of gaps in the lap stream, there is a risk of tail edges generating output
pulses. Such bent up tail edges can not be suppressed by means of a dead time
because the dead time would be triggered by the fold and had to practically cover
the whole length of a copy. But that means a dead time bigger than the overlap
leading to the unacceptable suppression of regular copies. However, if the pulse
output is delayed and a retro-reflective foil mounted, then the Scatec-10 / -15 can
nevertheless be set in such a way that bent up tail edges are completely
suppressed.
Therefore Scatec-10 / -15 is able to suppress interfering tail edges provided:
a retro-reflective foil mounted is mounted
the output pulse is delayed (C9 = on)
a suitable zone checked for tail edges is chosen (C13 = on or off)
A bent up tail edge is suppressed if it is followed by a gap within a specific time (or
distance). This time or distance therefore defines a zone on the copy where edges
will be suppressed as tail edges and can be set either equal to the dead time (dead
path) or equal to the ouput pulse delay chosen earlier.
In order to set the tail edge suppression correctly, follow the subsequent flowchart
and refer to the sketch below.
conveyor
Bent up tail edges
Fold
Cut side of the
newspaper
Retro-reflective
foil
Scatec-1x
running direction