GE IC220SDL953, User Manual, Page: 105 / 124

A
GFK-2731 Chapter A A-29
A 11.2 Shutdown times
The required shutdown time for the safety function is based on the response times of the
sensors used, the VersaSafe system, the actuator used, and the stopping time of the
system. The required shutdown time of the safety function can be determined from the
safety distances or the safety distances are defined based on the determined guaranteed
shutdown time.
The
guaranteed shutdown time for the safety function is based on the longest processing
time of the safe inputs involved in the safety function and the shutdown time of the safe
output (single-channel or two-channel) involved.
For the processing time of the safe inputs, please refer to the corresponding data sheets
for the safe input devices.
Figure A-8 Overview of shutdown times
This results in the following formula for t
SF
t
SF
= tS + t
IN
+ t
FWD_IN
+ t
OUT_LPSDO
+ t
FWD_OUT
+ t
OUT
+ tA + tSTOP
81520011
t
G
t
IN
t
A
t
S
t
SF
A B
t
STOP
t
FWD_IN
t
OUT_LPSDO
t
FWD_OUT
t
OUT
Table A-22 Key for formula and Figure A-8
Abbrevia-
tion
Meaning Note
A Demand of the safety function
B Safe state of the system
t
SF
Required shutdown time for the safety function Determined from the application, e.g., from the
required times according to the distance of a light
grid
t
S
Response time of the sensor Sensor data sheet
t
IN
Processing time of the input Safe input module user manual
t
FWD_IN
F-Watchdog time (communication) Specified by the user in VersaConf Safety for each
IC220SDL543 module
t
OUT_LPSDO
Shutdown time of the IC220SDL953 10 ms; see technical data "VersaSafe system" on
page 10-1
t
FWD_OUT
F-Watchdog time (communication) Specified by the user in VersaConf Safety for each
IC220SDL... module
Without forwarding to a satellite with outputs,
t
FWD_OUT
= 0.
t
OUT
Shutdown time of the output Safe output module user manual
Without forwarding to a satellite with outputs, t
OUT
=
0.