Phoenix Contact PSRmodular - Figure 5-173: Logic Block Diagram of the Network Safety Function

PSRmodular system
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PHOENIX CONTACT 109241_en_03
Figure 5-173 Logic block diagram of the network safety function
Switch-on condition for
network signal
The points below relate to the two data flow network diagrams (Figures 5-169 and 5-172):
1. The “network signal” (Net_out) between all base modules is logic “0”.
2. When the RESET command is actuated on one of the base modules, depending on the
configuration, all of the base modules in the network can be activated.
3. After setting the RESET command, the “network signal” (Net_out) is set to logic “1”, pro-
vided a logic “1” signal is present at the “Net_in” inputs of the base modules located in
the network.
4. The network signal is distributed to all base modules in series.
Switch-off condition for
network signal
The points below relate to the two data flow network diagrams (Figures 5-169 and 5-172):
1. After triggering the emergency stop command at any base module, the “network signal”
(Net_out) goes to logic “0”.
2. The next base module receives the switch-off command via the network signal (Net_in)
and passes it on (Net_out).
3. As a result of the previous signal sequence, the network signal is switched off via the
“Net_out” signal.
4. After unlocking the triggered emergency stop control device, the entire network can be
restarted via the reset signal. The system needs approximately four seconds to restore
all function block outputs that form the network.
Network parameters for calculating the PL
Architecture: Cat. 4
Diagnostic coverage: DC = 99%
Probability of dangerous failure for PSR-M-B1: PFH
d
= 6.86 E-09 (hours
-1
)
PSR-M-B2
1
INPUT OUTPUT
PSR-M-B2
2
PSR-M-B2
3
PSR-M-B2
4
LOGIC (NET)
– The maximum response time for the emergency stop shutdown is calculated using
the formula t
r
= [(212 ms * n) - 260 ms], where n = the number of base modules in
the network.
– The maximum response time for the emergency stop shutdown is calculated using
the formula:
– For PSR-M-B1 base module:
t
r
= 11.3 ms + [175.3 ms * (number of base modules - 1)]
– For PSR-M-B2 base module:
t
r
= 12.7 ms + [232.7 ms * (number of base modules - 1)]