Failure Behavior; Overview Of Failure Behavior; Output; Totalizer Output - Siemens SITRANS P DS III Operating Instructions Manual

7.8

Failure behavior

7.8.1

Overview of failure behavior

If the transducer block fails, the analog input and totalizer function blocks can adopt a value
preset by the user. If the output variables of the transducer block have the status "Bad" due
to an error, activate the failure behavior for the function blocks. The status "Unsure" then
accompanies the output or the totalizer output.
7.8.2

Output

Set the failure behavior in the analog input function block:
Table 7- 10
Failure behavior
The output value is set to the replace-
ment value.
Saving of the last valid output value.
The incorrectly calculated measured
value is on the output (shutdown logic
turned off).
To narrow down the cause of failure after the shutdown logic engages, read the measured
value (primary variables) or secondary variables including the status from SIMATIC PDM.
7.8.3

Totalizer output

Set the failure behavior in the totalizer function block:
Table 7- 11
Failure behavior
Stop
Safe operation
Operation
SITRANS P DS III/P410 with PROFIBUS PA
Operating Instructions, 02/2016, A5E00053276-08
Failure behavior of the analog input function block
Failure behavior of the totalizer function block
Description
Counting is stopped if there are input values with
the "Bad" status.
Counting continues with the last input value that
had the "Good" status prior to the failure.
The bad measured value is accompanied by the
status assigned to it by the transducer block.
Operator control functions via PROFIBUS
Description
The predefined safety preset value is
output.
The last valid output value is output.
The bad output value is accompanied by
the status assigned to it by the transducer
block.
7.8 Failure behavior
Status code
U_075
U_071
B_0xx
Status code
U_075
U_072
B_0xx
119