Near range
In close proximity (50 mm-wide area in front of the front screen), the detection capabil‐
ity of the safe multibeam scanner may be restricted.
4.3.3
Response time of the safe multibeam scanner
Overview
The response time of the safe multibeam scanner must be taken into account, among
other things, so that the safe multibeam scanner can be positioned in a suitable
location and the protective fields can be sized correctly.
The protective device’s response time is the maximum time between the occurrence of
the event leading to the sensor’s response and supply of the switch-off signal to the
protective device’s interface (for example OFF state of the OSSD pair).
The response time of the safe multibeam scanner depends, among other things, on the
set multiple sampling.
Influence of signal transmission
In addition to the protective device’s response time, further signal transmission and
processing also influence the time up until the end of the dangerous state. This
includes a control’s processing time and the response times of downstream contactors,
for example.
Further topics
•
4.3.4
Monitoring case switching
Overview
The safe multibeam scanner monitors all configured protective and warning fields in
parallel. After switching to another monitoring case, the safe multibeam scanner can
access the results for the now active protective and warning fields without delay. This
also applies if multiple sampling is configured.
The changeover signal is transmitted via the static control inputs.
Duration of the monitoring case switching
If an object has been detected in a non-active protective or warning field, the safe
multibeam scanner can process the corresponding result immediately after the moni‐
toring case is switched. In this case you need to take into account the time required to
perform the monitoring case switching.
t
CSR
= 17 ms + t
ID
Where
•
t
CRS
= Duration of monitoring case switching in milliseconds (ms)
•
t
ID
= Switch-on delay (configurable) in milliseconds (ms)
Compare the time required to perform the monitoring case switching with the response
time (
) of the safe multibeam scanner. If the response
time is exceeded, check whether your application requires countermeasures. For exam‐
ple, you can initiate switching earlier or reduce the vehicle speed in the case of mobile
hazardous area protection.
When specifying the time of monitoring case switching, also take into account the
signal propagation times to the safe multibeam scanner, e.g. the processing time of a
control.
PROJECT PLANNING
4
8025936/2021-01-08 | SICK
O P E R A T I N G I N S T R U C T I O N S | scanGrid2 I/O
19
Subject to change without notice
