B 5231 / H51q-MS (0605)
104
4.5.2 Shutdown ways in the H51q-MS system
In safety-related systems an independent 2nd safety shutdown is necessary. This is done by
the watchdog signal. At fault on the CPU or the I/O connection the watchdog shuts down all
safety-related outputs.
Figure 4: Shutdown ways in the H51q-MS system
I/O bus
I/O bus
I/O bus
I/O bus
T =
Safety related output module
B
S =
Shut via operating system
X = Lo
ic si
nal
down
IO-CON = Coupling module
WD = Watchdog
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