Ceia THS - Reading Features; Step-Ladder Mode; Picket-Fence Mode

THS – FI022GB2K8v3 --- V - MAINTENANCE
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Reading features
The number of scans performed on the code by the reader, and therefore its decoding capability, is influenced by the
following parameters:
• number of scans per second
• code motion speed
• label dimensions
• scan direction in respect to code motion
At least 5 scans during the code passage should be allowed to ensure a successful read.
Step-Ladder mode
BCR bar code reader
CMD code motion direction at LS speed
LB laser beam
Fig. II - 32
If scanning is perpendicular to the code motion direction ( “step ladder” mode), the number of effective scans
performed by the reader is given by the following formula:
SN = ((LH/LS) * 350) - 2
These symbols signify:
SN = number of effective scans
LH = label height (in mm)
LS = label movement speed (in mm/s)
For example, the reader for a 25 mm high code moving at 500 mm/s performs:
SN = ((25/500) * 350) - 2 = 15 effective scans
Suitable values for LH and LS should therefore be chosen, so that:
LH/LS > 0.02
Picket-Fence mode
BCR bar code reader
CMD code motion direction at LS speed
LB laser beam
Fig. II -33
If scanning is parallel to the code motion, (“picket fence” mode), the number of effective scans is given by:
SN = (((FW-LW)/LS) * 350) - 2
These symbols signify:
SN = number of effective scans
FW = reading field width (in mm)
LW = label width (in mm)
LS = label movement speed