Siemens Simatic S7-1500 Function Manual page 28

Cycle time statistics
You can read the cycle time statistics either directly from STEP 7 ("Online tools" task card)
or with the "RT_INFO" instruction.
You can use the "RT_INFO" instruction to generate statistics in STEP 7 on the runtime of
specific organization blocks for communication or for the user program. For example, this
includes
● The shortest and longest cycle time
● The portions of runtime used for communication and the user program
Note
Showing the cycle time statistics on the display and Web server
With the S7-1500 CPUs, you also have the option of calling the cycle time statistics via the
display of the CPU. As of firmware version 2.0 of the CPUs, the cycle time statistics are also
displayed in the Web server.
To view the cycle time statistics directly in STEP 7, follow these steps:
1. Establish an online connection to the CPU with STEP 7.
2. Select the "Online tools" task card.
Result: The diagram of the cycle time statistics is displayed in the cycle time section.
The following figure shows an extract from STEP 7 with the cycle time statistics. In this
example, the cycle time fluctuates between 7 ms and 12 ms. The current cycle time is 10
ms. The maximum cycle time that can be set in this example is 40 ms.
Figure 3-4
You can find additional information on the runtime characteristics of the CPU with the
"RT_INFO" instruction in the user program. The instruction includes information about:
● The utilization of the CPU by the user program and communication in percentage
● The runtimes of the individual OBs
Cycle and response times
Function Manual, 10/2018, A5E03461504-AD
Cycle time statistics
Cyclic program execution
3.2 Cycle time
27