SICK CLV 480, Operating Instructions Manual

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Chapter 6 Operating Instructions
CLV 480 Bar Code Scanner
6-12
©
SICK AG · Division Auto Ident · Germany · All rights reserved 8 010 080/O824/10-02-2005
Operation
contain bar codes during the time available. This also ensures that the scan line density on
the object is, for the most part, constant. Fig. 6-3 illustrates this mode when a bar code is
read from above.
3. "Fixed Position" mode
The CLV parks the oscillating mirror at the desired position. 10 CW corresponds to –20
°
,
and 90 CW to +20
°
(see Fig. 4-8, Page 4-6 ). In the default setting, the fixed position is set
to 50 CW (corresponds to an angle of deflection below 105
°
). The Oscillating mode is swit-
ched off.
4. "One-Shot" mode
In the "One-Shot" mode, the oscillating mirror only performs one specific oscillating move-
ment per reading interval. This movement consists of a forward phase and a return phase.
The start position of the scan line, the mirror speed and the valid distance configuration can
be parameterized separately for each phase. The end position of the one phase forms the
start position of the other phase. Fig. 6-4 illustrates this mode with object tracking. During
the forward phase, the front of the object that moves towards the oscillating mirror is swept
once by the scan line from top to bottom in accordance with the conveyor speed. Multiple
focus position switchovers are not necessary as the required reading range (DOF) is much
smaller than with the line scanner. Fig. 10-32, Page 10-43 explains how the start position
and mirror speed are calculated for a given conveyor speed.
Possible trigger sources for One-Shot:
•
"IN 3" or "IN 4" switching input
•
Command string (via serial interface)
•
Start of reading interval
Fig. 6-3: Oscillating mirror: "Oscillating with variable amplitude" mode
0 0
1
Constant
oscillating
frequency
Scan line density equal, independant of object height
Limitation of the
deflection range
(CW value)