Siemens SIMATIC PCS 7 Operating Manual page 141

The F-monitoring time must be calculated for the relevant variant of each F-signal module
type or each device, and the values for the cyclic interrupt OB must be calculated as well. To
do this, select the appropriate configuration variant and enter the parameters in the
corresponding line.
You need the following parameters for the calculation depending on the variant:
T
CI
T
PROG
T
CImax
T
DP_DLY
T
TR/TR1
T
TR2
T
DPPA_L_DLY
T
Y_L_DLY
T
Slave
T
DAT
With inputs
and outputs
T
DP_FD
T
DP_SO
T
SLAVE_SO
T
F-SIGNAL
MODULE, ACK
T
DP_DLY
Compendium Part B - Process Safety (V8.2)
Operating Manual, 07/2016, A5E35031794-AB
Configured execution time of the cyclic interrupt OB in which the F-module driver is
processed
Program runtime of the cyclic interrupt OB in which the F-module driver is processed
Time set at the F_CYC_CO block for scan cycle monitoring of the cyclic interrupt OB
Additional delay time with external DP interface (via CP 443-5 Extended)
Maximum target rotation time for the DP master system
Maximum target rotation time for the subordinate DP master system on the Y link, or
maximum target rotation time for the subordinate PA master system on the DP/PA
coupler
Delay time with a DP/PA link
Delay time with a Y link
Maximum delay time with IM 153-2 / IM 153-4 (typical value for ET 200M = 1 ms)
Maximum acknowledgment time of the fail-safe I/O module in safety mode (F signal
module group data sheet)
If you are using F-signal modules with inputs and outputs, set "Yes" here (e.g. ET
200pro). If you are using an ET 200M, set "No".
Maximum DP error detection time
Only relevant for redundant IM 153-2 (switched I/O).
Enter 0 if you are not using a redundant IM.
Maximum DP switchover time
Only relevant for redundant IM 153-2 (switched I/O).
Enter 0 if you are not using a redundant IM.
Max. switchover time of the slaves
Only relevant for redundant IM 153-2 (switched I/O).
Enter 0 if you are not using a redundant IM.
Maximum acknowledgment time of the fail-safe I/O module in safety mode (F signal
module group data sheet)
Additional delay time with external DP interface (via CP 443-5 Extended)
Configuring the safety program
7.11 Monitoring times and system response times
141