Handling Measured Value Archives - Siemens SIMATIC ET 200S Manual

Functions of the IM 151-7 CPU
Measured value archives
Measured values are created when the user program is processed by the
IM 151-7 CPU. These measured values are to be archived and evaluated.
Processing sequence of a measured value archive
Collecting the measured values:
S The measured values in the working memory are collected in a DB (for
alternating buffer operation in several DBs) by the IM 151-7 CPU.
Archiving the measured values:
S Calling the SFC 84 "WRIT_DBL" from the user program moves the measured
values in the DB to the load memory before the data volume can exceed the
memory capacity of the working memory.
Figure 8-7
S Calling the SFC 82 "CREA_DBL" from the user program generates new
(additional) DBs as non-process-related DBs in the load memory. These
non-process-related DBs do not require space in the working memory.
Note
If a DB with the same name already exists in the load memory and/or working
memory, the SFC 82 is terminated and an error display is generated.
The data written to the load memory is not erased by a memory reset and is
transferrable.
Evaluating the measured values:
S The measured value data blocks stored in the load memory can be uploaded
and evaluated by other communication partners (e.g. PD, PC, ...).
8-24
Load memory
(MMC)
Measured values 1
Measured values 2
:
Measured values n

Handling measured value archives

Working memory
(IM 151-7 CPU)
SFC 82
CREA_DBL
SFC 84
WRIT_DBL
ET 200S IM 151-7 CPU Interface Module
Current
measured values
A5E00058783-04