Siemens S7-300 Installation And Operating Manual page 277

Example
The following figure shows you the behavior of the discrepancy evaluation when standard
value = MAX.
The diagram above shows you the characteristic curve of the two process values. The
dashed line represents the absolute tolerance range configured in this example.
The lower diagram shows you the standard value signaled to the F-CPU.
In this example, on the first occurrence of a discrepancy, process value 1 is
tolerance range again
is not signaled.
In this example, on the second occurrence of a discrepancy, process value 1 is
tolerance range when the discrepancy time expires. As a result, a discrepancy is signaled
with 7FFF
value 0 is provided in the PII for the safety program in place of 7FFF
the fail-safe value assigned at the input SUBS_V of the channel driver will be provided in the
PII.
Fail-safe signal modules
Installation and Operating Manual, 01/2010, A5E00085586-10
before
expiration of the discrepancy time. This means the discrepancy
after expiration of the discrepancy time. In
H
9.3 SM 336; F-AI 6 x 0/4 ... 20 mA HART
S7 Distributed Safety
S7 F/FH Systems
. In
H
Analog modules
within
the
outside
the
, the fail-safe
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