4.3.3
Timing for monitoring case switching
Overview
When switching between monitoring cases, it is possible that a person may already be
in the newly activated protective field when switching takes place. Only by switching in
the correct time frame (i.e., before the hazard occurs at this point for the person) is pro‐
tection provided.
You must advance the switching time in the following situations:
•
You have entered an input delay for the switching method.
The following diagram illustrates the relationships:
1
2
3
t
t
UFVz3
t
UFVz2
t
UF
Figure 27: Advancing the switching time
•
If the input conditions are present on the control inputs within 10 ms and 20 ms
(cf.
1
), the switching time (t
UF
) does not need to be advanced.
•
If an input delay for the control inputs needs to be allowed for (cf.
2
), the switch‐
ing time (t
UFVz2
) must be advanced by the input delay.
•
If external OSSDs are used, the switching time (t
UFVz3
) must be advanced by an
additional 20 ms (cf.
3
).
Important information
DANGER
Ineffectiveness of the protective device
Persons or parts of the body to be protected may not be recognized or not recognized in
time in case of non-observance.
Someone may already be in the protective field at the time of switchover. Only by switch‐
ing in the correct time frame, i.e., before the hazard occurs at this point for the person,
is protection provided.
b
Time the switching so that the safety laser scanner detects a person in the protec‐
tive field at a sufficient minimum distance before the dangerous state occurs.
Example
The following figure shows a gantry robot that is protected by 2 monitoring cases.
4
PROJECT PLANNING
34
O P E R A T I N G I N S T R U C T I O N S | S3000 PROFINET IO, S3000 PROFINET IO-OF
8013291/ZA19/2019-11-14 | SICK
Subject to change without notice
