SICK WTT12-S Instrucciones De Funcionamiento página 13

8029123/2024/01/15 | SICK
Subject to change without notice
3
L
L
Figure 5: Presence of an object
Sensor
1
Light beam
2
Object
3
Background
4
"Operation" switching threshold
L
1
Teach-in point
L
2
"Test" switching threshold
L
3
The sensor needs to be taught-in to a reference surface (teach point L
The thresholds for the "Operation" and "Test" modes are derived from a defined offset,
see "Data sheet", page 30:
• Positive offset for "Test"
• Negative offset for "Operation"
This ensures a reliable and rugged use of the safety sensor.
In "Operation" mode, the output switches to ACTIVE if the measured distance is less
than L , i.e., an object is present between the sensor and the reference surface. If there
1
is no object present between the sensor and the reference surface (measured distance
> L ), the sensor remains INACTIVE. This represents the safety-related state.
1
The device can be switched between operating mode and test mode via a test input. In
test mode, the threshold value is shifted to L
now recognized as the object to be detected. The safety function is thereby requested
and checked for the correct response.
In test mode, the output should switch to INACTIVE if the measured distance is equal to
or less than L .
1
The following table shows the different states depending on the measured distance
(L ) and based on the set threshold (L
meas
Table 1: States depending on the measured distance at the set threshold
Distance
L ≤ L
meas 1
L < L ≤ L
1 meas 3
L > L
meas 3
To ensure a correct implementation of the safety function, the detection corridors in
section 4.6.1 must be taken into consideration.
OPERATING INSTRUCTIONS
L
so that the actual reference surface is
3
or L ).
1 3
Operation (L threshold)
1
Active
Inactive
Inactive
O P E R A T I N G I N S T R U C T I O N S | WTT12-S
1
2
4
).
2
Test (L threshold)
3
Inactive
Active
Inactive
en
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