Rockwell Automation 2755 AdaptaScan Bar Code Readers - Manual (Page 29)

Installation Considerations 2–3
The skew, pitch and tilt of a bar code symbol affect its readability.
Symbols that are pitched or skewed up to 45
_ are still readable.
Although some skew is needed (see below), it should not exceed
45
_. Symbols may be tilted if the scan beam passes through all bars.
Tilted
Symbol
Skewed
Symbol
No Tilt, Pitch,
or Skew
Pitched
Symbol
Mount the Reader so that the scan beam is nearly perpendicular to
the bars of the symbol and crosses every element and quite zone.
With raster scanning, the scan beam should cover the entire area
where a label is expected.
Quiet
Zone Quiet
Zone Quiet
Zone Quiet
Zone
Scan Beam
For optimum performance, mount the Reader so it scans the symbol
from a skewed position 20 to 30
_ from perpendicular to the symbol.
Skew Angle
20 _
20 _
= Optimum Reader
Mounting Angle
Top
Of Package
Side
Of Package
20 _
= Optimum Reader
Mounting Angle
30 _
30 _
20 _
30 _
Skew Angle
30 _
Skew, Pitch and Tilt
Recommended Skew Angle