Siemens SIMATIC PCS 7 Operating Manual page 157

F signal module
Compendium Part B - Process Safety (V8.2)
Operating Manual, 07/2016, A5E35031794-AB
T
WCDT
Response time with 1oo1 evaluation (operation with and without errors)
•
Response time = Internal processing time
up time of the sensor after sensor test}2)
Response time at 1oo2 (2v2) evaluation with discrepancy behavior = "provide 0 value"
•
(operation with and without errors)
Response time = Internal processing time
CHANNEL(n) + start-up time of the sensor after sensor testCHANNEL(n)
sensor testCHANNEL(n+4) + start-up time of the sensor after sensor testCHAN-
NEL(n+4)) }
2),3)
Response time at 1oo2 (2v2) evaluation with discrepancy behavior = "Provide last valid
•
value" (operation without errors)
Response time = Internal processing time
sensor test CHANNEL(n) + start-up time of the sensor after sensor testCHANNEL(n))
(time for sensor test CHANNEL(n+4) + start-up time of the sensor after sensor
testCHANNEL(n+4))
2),3)
ed. This repetition only has an effect on the response time for 1oo2 (2v2) evaluation with
discrepancy behavior = "Provide last valid value".
Response time for 1oo2 (2v2) evaluation with discrepancy behavior = "provide last
•
valid value" (operation with errors)
Response time = Internal processing time
for sensor testCHANNEL(n) + start-up time of the sensor after sensor testCHAN-
NEL(n)) + (time for sensor testCHANNEL(n+4) + start-up time of the sensor after sen-
2)
sor testCHANNEL(n+4))
Explanations:
Internal processing time dependent on parameter assignment – see above table "Internal
1)
processing time of the EM 8 F-DI Ex NAMUR based on parameter assignment"
Response time dependent on the sensor supply test parameter:
2)
Deactivated: For the times within the bracket terms zero values are to be inserted
•
Activated: For the times within the bracket terms the values from assigned parameters
•
are to be inserted
Response time is based on the sensor supply parameter at 1oo2 (2v2):
3)
Sensor n and n+4 to Vs n: For the times within the bracket terms zero values are to be
•
inserted
Each sensor to separate Vs: For the times within the bracket terms the values from as-
•
signed parameters are to be inserted
7.11 Monitoring times and system response times
T
OFDT
+ Input delay + {Time for sensor test + start-
1)
+ input delay + MAX { (time for sensor test
1)
+ input delay + discrepancy time + (time for
1)
If there is an error with the sensor supply test, the test is repeat-
+ input delay + discrepancy time + 2 x { (time
1)
}
2),3)
Configuring the safety program
, (time for
)2)
+
2)
157