Example Program For Data Logging - Siemens S7-1500 Function Manual

Note
Asynchronous instructions
Note that the instructions in the table are asynchronous instructions.
In contrast to synchronous instructions, this means the execution of an asynchronous
instruction can extend over multiple calls before execution is completed. The CPU processes
asynchronous instructions in parallel with the cyclic user program.
A CPU can process several asynchronous instruction jobs in parallel. The CPU can process
a maximum of 10 jobs of the instructions listed in the table in parallel.
You can find additional information about asynchronous instructions in the following
manuals:
• System manual S7-1500, ET 200MP
(http://support.automation.siemens.com/WW/view/en/59191792)
• System manual ET 200SP Distributed I/O System
(https://support.industry.siemens.com/cs/ww/en/view/109482416)
• Operating instructions ET 200pro CPU 1516pro-2 PN
(https://support.industry.siemens.com/cs/ww/en/view/109482416)
3.2.4

Example program for data logging

This example program shows the storing of process values for counter content, temperature,
and pressure in a data log.
The example shows the basic functioning of the instructions for data logs. The complete
program logic is not shown.
Note
General use of data logs
• Data logs are automatically opened after execution of the "DataLogCreate" and
"DataLogNewFile" instructions.
• Data logs are automatically closed at a change of the CPU from RUN to STOP or a
restart of the CPU.
• A data log must be open so that data can be written to the data log with the
"DataLogWrite" instruction.
• A maximum of 10 data logs can be open at any one time, even when more than 10 data
logs exist.
Structure and Use of the CPU Memory
Function Manual, 10/2018, A5E03461664-AC
Memory usage and application examples
3.2 Memory usage for data logging
47