Siemens Simatic ET 200pro FC, Руководство по эксплуатации

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Commissioning and optimization (software)
7.4 Commissioning of communication between the S7 CPU and the frequency converter
ET 200pro FC
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Operating Instructions, 07/2016, A5E01100763B AC
7.4.3.2 Examples
Writing PROFIdrive parameters
In order to make use of DS47, a data block first needs to be created in Simatic Manager.
This implements the data set structure using the parameter request table as a template. In
this example, a data set is stored in DB47 for the purpose of changing P1082 (maximum
frequency).
P1082 is to be changed to 100 Hz.
Image 7-5 DB47 (DS47 write job)
This data set is then sent to the FC in the context of cyclic program execution (e.g., OB1)
using SFC58.
In order to be able to read the reply data set from the FC, an additional data block again
needs to be created. For this purpose, DB1 is added to the project. To ensure as flexible a
response as possible, DB1 is created as a data field with a length of 240 bytes and no
defined structure. The response must then be evaluated on a request-specific basis.
Image 7-6 DB1 (DS47 response)
Once the data blocks have been created, a parameter request is written via data set DS47
using S7 function SFC58. Then, a reply data set is read with SFC59 and stored in DB1. In
this example, the start of this process is triggered by a positive edge at input In0.0.