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6.2 PCV Parameter Access
Parameter access via the PCV channel is performed by the PROFINET cyclical data exchange, where the PCV channel is part
of the PPOs described in
chapter 6 How to Control the Frequency Converter
.
Using the PCV channel it is possible to read and write parameter values, as well as readout of a number of describing
attributes of each parameter.
6.2.1 PCA Handling
The PCA part of PPO types 1, 2 and 5 can handle several tasks. The master can control and supervise parameters and
request a response from the slave, whereas the slave can respond to a request from the master.
Requests and responses
is a
handshake procedure and cannot be batched, meaning that if the master sends out a read/write request, it has to wait for
the response, before it sends a new request. The request or response data value will be limited to maximum 4 bytes, which
implies that text strings are not transferable. For further information, see
chapter 9 Application Examples
.
6.2.2 PCA - Parameter Characteristics
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
RC
SMP
PNU
Table 6.2 PCA - Parameter Characteristics
RC: Request/response characteristics (Range 0..15)
SMP: Spontaneous Message (Not supported)
PNU : Parameter no. (Range 1..1999)
How to Control the Frequenc...
Operating Instructions
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Danfoss A/S © Rev. 2014-02-27 All rights reserved.
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Содержание VLT PROFINET MCA 120
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