Figure 1: Alignment
7.2 Check the application conditions
WTF26 are photoelectric proximity sensors with foreground suppression. The photoelec‐
tric proximity sensor requires a background as a reference. The remission and position
of the background should remain as uniform as possible. The maximum distance (x)
between the photoelectric proximity sensor and background as well as the minimum
object height (y) must be upheld.
As a rule, a WTF26 is used to detect very flat objects on a conveyor belt.
Check the application conditions: Compare distance between sensor and background,
minimal object height as well as radiance capability of background and object with the
associated diagram (see figure 2, page 8) (x = sensing range, y = minimum object
height). Remission: 6% = black 1, 90% = white 2 (referring to standard white as per DIN
5033).
Example: x = 500 mm, y = 11 mm, i.e. a white object is detected from a height of
at least 11 mm on a black background. The distance between photoelectric proximity
sensor and background is 500 mm.
Table 6: Application conditions
x
y
6%/6%
6%/90%
90%/90%
90%/6%
4
1
3
2
WTF26P-xxxxx4xx
Example:
Sensing range on black background, 6%,
x = 500 mm, y = 11 mm for white object
Background
y
x
0
5
10
15
25
20
30
100
(3.94)
200
(7.87)
300
(9.84)
400
(15.75)
600
(23.62)
500
(19.69)
0
Distance in mm (inch)
Minimum object height
in mm (y)
35
40
700
(27.56)
800
(31.50)
Figure 2: Characteristic line: WTF26
1
Black object, 6% radiance factor, in front of
black background, 6% radiance factor
2
Black object, 6% radiance factor, in front of white
background, 90% radiance factor
3
White object, 90% radiance factor, in front of
black background, 6% radiance factor
4
White object, 90% radiance factor, in front of
white background, 90% radiance factor
1
2
200
(7.87)
800
(31.50)
D
Distance in mm (inch)
A
BluePilot:
B
C
E
F
A Sensing range min. in mm
B Sensing range max. in mm
C Viewing range
D Adjustable switching thresh‐
old for foreground suppres‐
sion
E Sensing range indicator
F Teach-Turn adjustment
1
Sensing range on black, 6%
radiance factor
2
Sensing range on white, 90%
radiance factor
7.3 Sensing range setting
WTF26x-xxxxxx2xAxx with Teach-Turn adjustment:
7 COMMISSIONING
8
8025684.9RH / 15.01.2021 | SICK
Subject to change without notice