Reproducibility Of Time-Delay And Watchdog Interrupts Of The Cpus - Siemens SIMATIC S7-400 Reference Manual

3.10 Reproducibility of Time-Delay and Watchdog Interrupts
Definition of "Reproducibility"
Time-delay interrupt:
The deviation with time from the first instruction of the interrupt OB being called to
the programmed interrupt time.
Watchdog interrupt
The variation in the time interval between two successive calls, measures between
the first instruction of the interrupt OB in each case.
Reproducibility
Table 3-11 contains the reproducibility of time-delay and watchdog interrupts of the
CPUs.
Table 3-11 Reproducibility of Time-Delay and Watchdog Interrupts of the
Baugruppe
CPU 412-1/-2
CPU 414-2/-3
CPU 416-2/-3
CPU 417-4
CPU 41x-4H
single mode
CPU 41x-4H redundant
These times apply only if the interrupt can be executed at this time and not, for
example, delayed by interrupts with higher priority or interrupts of identical priority
that have not yet been executed.
Automation System S7-400 CPU Specifications
A5E00165965-01
CPUs.
Time-Delay Interrupt:
–770 ms / +330 ms
–770 ms / +330 ms
–770 ms / +330 ms
–770 ms / +330 ms
–750 ms / +400 ms
–500 ms / +800 ms
Cycle and Reaction Times of the S7-400
Reproducibility
Watchdog Interrupt
–40 ms / +40 ms
–40 ms / +40 ms
–40 ms / +40 ms
–40 ms / +40 ms
–850 ms / +850 ms
–700 ms / +700 ms
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