Rockwell Automation 2755 High Performance VLD Scanner - Manual (Page 19)

3–6 Installation Considerations
Figures 3.6 and 3.7 show the Usable Beam Length versus Distance
for the LD4 scanners. The black area is a no read area. The Usable
Beam Length (bottom of chart) is compared to the Reading Distance
(top of chart). The Usable Beam Length is approximately 20% less
than the projected beam length (10% on each end of the scan line).
The reading distance is measured from the scan window to the center
of the symbol.
Figure 3.6
LD4A, B, C Usable Beam Length ➀
4.9
12.4
8.1
20.6
11.4
28.9 14.6
37.1 17.9
45.4 21.1
53.7 24.4
61.9 27.6
70.2 30.9
78.4 Inches
Centimeters
Usable Beam Length (Nominal)
NA
NA
5
12.7
10
25.4
15
38.1
20
50.8
25
63.5
30
76.2
35
88.9
40
101.6
45
114.3
Inches
Centimeters
NA
NA
LD4A, B, C Reading Distance
Usable
Beam
Length
= Catalog No. 2755-LD4A, B, C
= No Read Area
Reading Distance
➁
50
127.0
34.1
86.7
➀ Usable Beam Length for LD4A, B, C Scanners = 0.65 x (Reading Distance + 2.5 inches)
Measured from the scan window to the center of the bar code symbol. ➁
2755-LD4
Usable Beam Length
(A,B,C Ranges)