Symbol MiniScan MS-120X, Integration Manual

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2-16
MS-120X and MS-220X Integration Guide
4. Center the symbol (left to right) in the scan line whenever possible.
5. Position the symbol so that the scan line is as near as possible to perpendicular to
the bars and spaces in the symbol.
6. Avoid specular reflection (glare) off the symbol by tilting the top or bottom of the
symbol away from the scanner. The exact angle is not critical, but it must be large
enough so that if a mirror were inserted in the symbol location, the reflected scan
line would miss the front surface of the scanner. For the maximum allowable angles
refer to the Skew, Pitch and Roll angles listed in each MiniScan
Technical
Specifications table.
7. If an additional window is to be placed between the scanner and the symbol,
determine the optimum symbol location using a representative window in the
desired window position. Review the sections of this chapter concerning window
quality, coatings and positioning.
8. Give the scanner time to dwell on the symbol for several scans. When first enabled,
the MiniScan may take two or three scans before it reaches maximum
performance. Enable the MiniScan before the symbol is presented, if possible.
Conveyor Applications
Conveyor applications require setting the conveyor velocity to optimize the scanner’s ability
to read symbols. Also consider the orientation of the symbol with respect to the conveyor
direction.
Figure 2-13 on page 2-17 illustrates the relationship of the conveyor velocity with
respect to a symbol positioned perpendicular to the conveyor direction and Figure 2-14 on
page 2-18 illustrates the relationship of the conveyor velocity with respect to a symbol
positioned parallel to the conveyor direction.
Symbol is Perpendicular to Conveyor Movement
With the symbol bars perpendicular to the conveyor belt direction (Picket Fence
presentation) the relationship is:
V = (R x (F-W)) / N
Where: V = Velocity of the conveyor (inches/second)
R = Scan Rate (see technical specifications)
F = Field width of scan beam
W = Symbol Width (inches)
N = Number of scans over symbol (minimum of 10 scans)