Run Operating State - Siemens SIMATIC S7-1500 System Manual

Points to note
The STOP operating state results in a frame failure at the drive with a corresponding response
at the drive end (for example, OFF3 fast stop, depends on parameter assignment). You can
find additional information in the SINAMICS S120 Communication function manual
(https://support.industry.siemens.com/cs/ww/de/view/109781721/en).
13.4.4

RUN operating state

Response
Cyclic, time-driven, and interrupt-driven program execution are performed in RUN. Addresses
in the "Automatic update" process image are automatically updated in each program cycle.
You can also find more information in Process images and process image partitions
(Page 157).
Execution of the user program
Once the CPU has written the outputs and read the inputs, it executes the cyclic program
from the first instruction to the last instruction. Events with a higher priority, such as
hardware interrupts, diagnostic interrupts, Motion Control functions and communication, can
interrupt the cyclic program flow and prolong the cycle time.
If you have configured a minimum cycle time, the CPU will not end the cycle until this
minimum cycle time has expired, even if the user program is completed sooner.
The operating system monitors the execution time of the cyclic program for a configurable
upper limit known as the maximum cycle time. You can restart this time monitoring at any
point in your program by calling the RE_TRIGR instruction.
If the cyclic program exceeds the maximum cycle time, the operating system will attempt to
start the time error OB (OB 80). If the OB does not exist, the CPU ignores the maximum cycle
time overshoot. If the cycle monitoring time is exceeded for a second time, for example while
the time error OB is being processed, the CPU switches to STOP.
Additional information
You can find additional information on cycle and response times in the Cycle and Response
Times (https://support.industry.siemens.com/cs/ww/en/view/59193558) function manual.
SIMATIC Drive Controller
System Manual, 11/2023, A5E46600094-AD
Commissioning
13.4 Operating states of the CPU
275