Extending The Cycle By Nesting Interrupts; Calculation Examples For Cycle Time And Response Time - Siemens SIMATIC S7-300 Series Reference Manual

Cycle and Reaction times

Extending the Cycle by Nesting Interrupts

Table 3-6 shows typical extensions of the cycle time through nesting of an
interrupt. The program runtime at the interrupt level must be added to these. If
several interrupts are nested, the corresponding times need to be added.
Table 3-6 Extending the Cycle by Nesting Interrupts
Interrupts 312 IFM
Hardware approx. approx.
<FJ>interr
840 ms 700 ms
upt
Diagnostic – approx.
interrupt
880 ms
Time–of–d –
ay
interrupt
Delay –
interrupt
Watchdog –
interrupt
Programm – approx.
ing/
740 ms
access
error/
program
execution
error
3.3

Calculation Examples for Cycle Time and Response Time

Component Parts of the Cycle Time
As a reminder: The cycle time comprises:
S process image transfer time +
S operating system processing time +
S user program processing time +
S Processing time of S7 timers
3-10
313 314 314 IFM
approx. approx.
700 ms 730 ms
approx. approx.
880 ms 1000 ms
– approx. approx.
680 ms 700 ms
– approx. approx.
550 ms 560 ms
– approx. approx.
360 ms 380 ms
approx. approx.
740 ms 760 ms
PLC S7-300, CPU Specifications CPU 312 IFM to CPU 318-2 DP
315 315-2 DP 316-2DP
approx. approx. approx.
480 ms 590 ms 590 ms
approx. approx. approx.
700 ms 860 ms 860 ms
approx. approx. approx.
460 ms 560 ms 560 ms
approx. approx. approx.
370 ms 450 ms 450 ms
approx. approx. approx.
280 ms 220 ms 220 ms
approx. approx. approx.
560 ms 490 ms 490 ms
318-2
approx.
340ms
approx.
450 ms
approx.
350 ms
approx.
260 ms
approx.
260 ms
approx.
130/ 155/
285 ms
A5E00111190-01