WARNING
Risk of ineffectiveness of the protective device!
Undetected errors and faults can cause impairment, reduction or complete loss of
detection capability, such that the device is no longer able to perform the safety
function.
8.4
Environmental influences
The measurement by means of the time-of-flight method is well established and is
used in the single-echo method employed here only in the protected area (indoors)
in order to avoid inadvertent shadowing. This enables disturbances due to moisture,
precipitation and contamination to be minimized.
The device reacts to temperatures and different remissions at various distances with a
systematic mismeasurement. To minimize this, the systematic error can be minimized
by means of the teach-in function.
If the sensor is likely to be contaminated, a reserve against reduced detection capa‐
bility should be factored in and additional monitoring of the signal quality or signal
strength is recommended.
The ObSB function is provided to prevent misalignment caused by, for example, vibra‐
tion or impact.
Excessive light on the target or in the sensor may reduce the detection capability.
Avoiding reflectors and thereby reducing the presence of diffusely reflecting objects
increases the detection capability due to a lower dynamic range of the remission.
Measurement or distance determination on reflectors (as the target object) in a safety-
related context is not permitted.
Faults or errors that lead to loss of detection capability (e.g., due to environmen‐
tal influences) are covered within the maximum downtime per year required by
IEC TS 62998-1. This corresponds to a maximum of 5 minutes per year for Perform‐
ance Class B. This also specifically takes into account any undetected corrupted mes‐
sages that may occur during data communication due to electromagnetic ambient
conditions.
8.5
Fault exclusions
No fault exclusions have been specified for the device. The occurrence of faults can
result in the loss of the
safety function
.
8.6
Manipulation
The device does not have any protective measures against manipulation, especially
none that relate to the optical system. Objects, especially objects covering the viewing
window and/or in the blind zone, are not detected by the device, causing impairment,
reduction or complete loss of detection capability, and the device no longer being able
to perform the safety function.
Manipulations with effects similar to undetected errors (
) are also not detected.
ERROR BEHAVIOR
8
8027663//2022-08-04 | SICK
O P E R A T I N G I N S T R U C T I O N S | DT35S
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Subject to change without notice