Siemens SIRIUS 3RK3 Equipment Manual page 182

Operation
6.1 Response times
Formula
t
CYCLasi
t
RL
t
FRL
t
OUT
t
A
t
FB
Example 3
①
②
③
④
⑤
⑥
Figure 6-12
This case considers the signal flow from an EMERGENCY STOP on an input of an MSS 3RK3
Advanced via the AS-i bus (direct data exchange) to another MSS 3RK3 Advanced and then to an
actuator (contactor) via the output terminal of an expansion module.
The EMERGENCY STOP transmits an OFF signal to the first MSS 3RK3 Advanced. This unit
processes the signal in its logic. After taking input delay times and timer functions in the logic
into account, it forwards the information to the AS-i bus via a simulated AS-i input slave. The
second MSS 3RK3 monitors this safety-related AS-i input slave and, in turn, processes the
information in its logic. After taking input delay times and timer functions in the logic into
account, the second MSS 3RK3 Advanced opens the contactors of the system via two safety-
related outputs.
182
Description
Transmission duration of the signals evaluated by the AS-i input slave (ASI IN) via the AS-i bus
up until the logic of the MSS 3RK3:
AS-i cycle time, max. 5 ms
Reaction time of the logic of the MSS 3RK3 in error-free operation
Fault reaction time of the logic of the MSS 3RK3; for single-channel actuator wiring not equal
to t
RL
Transmission duration from the logic of the MSS 3RK3 to the output terminal on the expan‐
sion module (EM Q)
• Semiconductor outputs: 10 ms
• Relay outputs: 20 ms
For the reaction time of the actuator (A), see the documentation of the actuator
Max. read-back time of the safety-related outputs:
• MSS 3RK3 central units
• 2/4 F-DI 2F-DO expansion module
• 4F-DO expansion module
1 2
AS-i master
AS-i power section
MSS 3RK3 Advanced No. 1
Fail-safe EMERGENCY STOP
MSS 3RK3 Advanced No. 2
Contactors
Configuration MSS 3RK3 Advanced - example 3
1 ms
1 ms
5 ms
3 4
Equipment Manual, 07/2020, NEB926253002000/RS-AC/006
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5
SIRIUS 3RK3 Modular Safety System