Siemens SIMATIC S7-400H System Manual page 162

Link-up and update
12.4 Time monitoring
6. Based on your user program, determine:
7. For each DP master system this results in:
8. Derived for each IO subsystem:
9. Select the minimum of all T
10. Define the share of the maximum inhibit time for I/O classes > 15 determined by the
11. Using the information in section Performance values for link-up and update
12. The recommended value for the maximum inhibit time for priority classes > 15 is now
162
– The cycle time of the highest-priority or selected (see above) cyclic interrupt (T
– The execution time of your program in this cyclic interrupt (T
T (DP master system) = T
P15
T (IO subsystem) = T
P15
NOTICE
If T (DP master system) < 0 or T
P15
Possible remedies are shown below the following example calculation. Make
appropriate changes and then restart the calculation at 1.
This time is then known as TP15_HW.
minimum I/O retention time (T
T = 50 ms + min. I/O retention time [2]
P15_OD
NOTICE
If T > T , stop the calculation here. Possible remedies are shown below the
P15_OD P15_HW
following example calculation. Make appropriate changes and then restart the
calculation at 1.
(Page 166), calculate the share of the maximum inhibit time for priority classes > 15
defined by the user program (T
NOTICE
If T > T , stop the calculation here. Possible remedies are shown below the
P15_AWP P15_HW
following example calculation. Make appropriate changes and then restart the
calculation at 1.
obtained from:
T MAX (T , T
P15 = P15_AWP
- (2 x T + T
PTO TR WA
- (2 x T + T
PTO max_Akt WA
(IO subsystem) < 0, stop the calculation here.
P15
(DP master system) values.
P15
):
P15_OD
).
P15_AWP
) [3]
P15_OD
)
PROG
+ T + T + T
PROG DP_UM SLAVE_UM
+ T + T + T
PROG PN_UM Device_UM
System Manual, 03/2012, A5E00267695-11
)
WA
) [1]
) [1]
S7-400H