Intermec 3010 Istruzione Sull'Installazione

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MaxiScan 3300 – Installation Guide – Edition 2.0
1  Before you start
Reading moving bar codes
Choosing between picket fence and ladder reading
Picket fence reading generally requires more scans per code in pass-through appli-
cations than with ladder reading.
Ladder reading generally requires fewer scans per code in pass-through applica-
tions than with picket fence reading, and can read over the whole code height, which
is good for high-speed pass-through with variable label quality and different label
positions.
Picket fence reading
picket fence
Calculating pass-through speed:
number of scans =
scan rate x (scan width - code width)
pass-through speed
- 2
Example:
scan width
=
20 cm
code width
=
10 cm
scan rate
=
450 scans/sec
conveyor speed
=
1 meter / sec  (100 cm / sec)
[ 450 * (20 - 10)  / 100 ] - 2 = 43  so there will be 43 full scans on the code
The code width value will vary slightly according to the degree of tilt and pitch.