Cycle And Reaction Times Of The S7-400 - Siemens SIMATIC S7-400 Reference Manual

Cycle and Reaction Times of the S7-400

This chapter explains the composition of the cycle and reaction times of the
S7-400.
You can display the cycle time of your user program on the relevant CPU using the
programming device (see manual Configuring Hardware and Communication
Connections with STEP 7 Version 5.0 or higher).
Examples will illustrate how you calculate the cycle time.
The reaction time is important for monitoring a process. This chapter provides a
detailed description of how to calculate this. If you use a CPU 41x-2 DP as a
master in the PROFIBUS DP network, you also have to take into account DP
cycle times (see Section 3.5).
Chapter Overview
Section
3.1
3.2
3.3
3.4
3.5
3.6
3.6
3.8
3.9
3.10
Further Information
You will find further information on the following processing times in the S7-400
Instruction List. It lists all the STEP 7 instructions that can be processed by the
relevant CPUs, together with their execution times and all the SFCs/SFBs
integrated in the CPUs and the IEC functions that can be called in STEP 7,
together with their processing times.
Automation System S7-400 CPU Specifications
A5E00165965-01
Cycle time
Cycle Time Calculation
Different Cycle Times
Communication Load
Reaction Time
How Cycle and Reaction Times Are Calculated
Examples of Calculating the Cycle Time and Reaction Time
Interrupt Reaction Time
Example of Calculating the Interrupt Reaction Time
Reproducibility of Time-Delay and Watchdog Interrupts
Description
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3-1