SICK WT34 Instrucciones De Operación página 11

8009202.11O1 | SICK
Subject to change without notice
WT34 are photoelectric proximity sensors with background suppression. Depending on the
remission of the object to be detected, and perhaps the background behind it, a minimum
distance (y) between the set sensing range (x) and the background should be maintained.
Remission: 6% = black 1, 18% = gray 2, 90% = white 3 (referring to standard white as
per DIN 5033). We recommend that the adjustment be performed with an object of low
remission.
The minimum distance (= y) for the background suppression can be determined from the
diagram [figure 5 1] as follows:
Example: x = 600 mm, y = 4.5 => 4.5% of 600 mm = 27 mm. That is, the background is
suppressed at a distance of > 627 mm from the sensor.
y
10
8
6
6%/90%
1
4
2
0
mm 200 400 600 800
Figure 5: WT34-Xx4x, -Xx5x, red light
y
10
8
6
6%/90%
1 18%/90%
4
2
0
mm 500 1000 1500
Figure 6: WT34-Xx1x, -Xx2x, infrared
light
3 Sensing range setting
Sensor with potentiometer: open the sensor cover and protective hood, make sure that no
dirt has gotten into the device.
The sensing range is adjusted with the potentiometer (type: without stop ). Clockwise rota‐
tion: sensing range increased; counterclockwise rotation: sensing range reduced. We rec‐
ommend placing the object within the sensing range, e.g. see
range has been adjusted, the object is removed from the path of the beam, which causes
the background to be suppressed and the switching output to change [see
figure 6].
18%/90%
2
x = 600 mm, y = 27 mm
(= 4.5% of 600 mm)
90%/90%
3
1
2
x
1000 1200 1400
3
Distance in mm
A = Detection distance (depending on
object remission)
B= Adjustment range
2
x = 1,000 mm, y = 30 mm
(= 3% of 1,000 mm)
90%/90%
3
1
2
x
2000 2500 3000 3
Distance in mm
A = Detection distance (depending on
object remission)
B= Adjustment range
COMMISSIONING
white back-
ground (90%)
x y
100 600
100 900
100
A B
white back-
ground (90%)
x y
100 1,300
100 1,800
100
A B
table 8. Once the sensing
figure 5
8
1,200
2,500
and
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