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
Properties of the parameter channel
● One 16-bit address for each parameter number and subindex.
● Transfer of different parameters in one access (multiple request).
● Entire fields or parts of fields can be transferred.
● Only one parameter request is processed at a time (no pipelining).
● A parameter request/response must fit into a data set (on PROFIBUS: max. 240 bytes).
● The header of the task or the response are user data.
● Only 1 master or 1 supervisor on a frequency converter can be cyclically accessed at a
time.
Structure of parameter request and parameter response
Each parameter request consists of three parts:
Request header:
ID for the request and number of parameters being accessed.
Parameter address:
Addressing a parameter. If multiple parameters are being accessed there will be a
corresponding number of parameter addresses. The parameter address appears in the
request and not in the response.
Parameter value:
For each parameter addressed there is a segment for the parameter values. Depending on
the request ID, the parameter values appear either only in the request or in the response.