5 Functional Mechanisms of this Application
5.2 Parameter access functionality
SINAMICS G120 DP at S7-1200
Entry-ID: 70155469, V1.4, 07/2018
Siemens AG 2018 All rights reserved
5.2.2 The DBs “read/write_drive_parameters” and “answer_from_drive”
The job to access a parameter consists of at least 10 words. Therefore, the job
should be assembled in a DB or in the temporary data of a code block. In this
example, this is performed using DB 101 “read_drive_parameters” and DB 100
“write_drive_parameters”.
The response by the SINAMICS converter also consists of several words.
Therefore, the example uses DB 103 “answer_from_drive”.
A job may contain the access to several parameters. Since the length of the data to
be transferred per job depends on the number and data types of the converter
parameters, no generally valid structure can be devised.
Therefore, in this example, only the ramp-up and ramp-down times (P1120 and
P1121) and a part of the fault memory (P945.x) is accessed. The job to read the
parameters is stored in DB 101 “read_drive_parameters”. The job to write them is
stored in DB 100 “write_drive_parameters”.
The response of the SINAMICS converter is copied to DB 103
“answer_from_drive”. The structure contained therein corresponds to the structure
for a successful reading of the parameters.
Place the entire job into a structure (in this example: “record”). This gives you the
option to symbolically address the data set via the structure name (here “record”)
with the RDREC/WRREC instructions.
Figure 5-8: DB100 “write_drive_parameters”
Run-up time parameter no.
Ramp-down time parameter no.
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