Chapter
4
Operating Instructions
CLV 490 Bar Code Scanner
4-6
©
SICK AG · Division Auto Ident · Germany · All rights reserved
8 009 993/O824/20-12-2004
Installation
Note
In oscillating mode with variable amplitude, the scan line must always sweep the neutral
position (CW = 50). This means that oscillation is not possible in the range 60 CW to 80 CW,
for example, but is possible in the range 40 CW to 80 CW.
4.2.8
Count direction of the code position CP and code angle CW
Explanation
The CLV can scan and decode several bar codes with each read. In doing so, it determines
the specific local reading diagnosis data for each bar code:
•
The position (CP value) of the center of the bar code within the scan line
•
(Scanning method using the oscillating mirror) also the angle of deflection of the scan
line (CW value) at which the center of the bar code is recorded
shows the count direction of the code position and code angle. In the case of the
line scanner, the count direction of the code position is marked by a small triangle above
the reading window.
By determining this data, the device can separate identical bar codes (code type, code
length, and data content identical) and assign the bar code data in the reading result to its
position on the object.
Tip
In the default setting, the CLV does not output the "CP" and "CW" values (line scanner with
oscillating mirror only) in the reading result on the host interface. If this is required to
evaluate the result in the host, the values can be included in the "Code-Info/Separator"
block of the output string using the "CLV-Setup" program.
Fig. 4-8:
Count direction of the code position CP in the scan line and of the code angle CW for the
oscillating mirror
100
CP
0
Line scanner
Line scanner with
oscillating mirror
Scanning direction
Aperture angle
α
(opening angle) in the scanning direction: 1
°
= 1.5 CP (56
°
= 90 CP)
Deflection angle of the scan line crosswise to the scanning direction: 1
°
= 2 CW (20
°
= 40 CW)
90
CW
10
100
CP
0
