Danfoss VLT FC 103, Руководство по конструкции

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are of different lengths. The telegram length is defined in
the second byte of the telegram, LGE. When using text
transfer, the index character indicates whether it is a read
or a write command.
To read a text via the PWE block, set the parameter
command (AK) to F hex. The index character high-byte
must be 4.
Some parameters contain text that can be written to via
the fieldbus. To write a text via the PWE block, set the
parameter command (AK) to F hex. The index characters
high-byte must be 5.
PWE
high
PWE
low
Read text
Write text
130BA275.10
PKE IND
Fx xx 04 00
Fx xx 05 00
Illustration 3.51 Text via PWE Block
3.9.7.11 Supported Data Types
Unsigned means that there is no operational sign in the
telegram.
Data types Description
3 Integer 16
4 Integer 32
5 Unsigned 8
6 Unsigned 16
7 Unsigned 32
9 Text string
10 Byte string
13 Time difference
33 Reserved
35 Bit sequence
Table 3.29 Supported Data Types
3.9.7.12 Conversion
The various attributes of each parameter are shown in
factory setting. Parameter values are transferred as whole
numbers only. Conversion factors are therefore used to
transfer decimals.
Parameter 4-12 Motor Speed Low Limit [Hz] has a conversion
factor of 0.1. To preset the minimum frequency to 10 Hz,
transfer the value 100. A conversion factor of 0.1 means
that the value transferred is multiplied by 0.1. The value
100 is therefore read as 10.0.
Examples:
0 s
⇒
conversion index 0
0.00 s
⇒
conversion index -2
0 ms
⇒
conversion index -3
0.00 ms
⇒
conversion index -5
3.9.7.13 Process Words (PCD)
The block of process words is divided into 2 blocks of 16
bits, which always occur in the defined sequence.
PCD 1 PCD 2
Control telegram (master
⇒
slave control word) Reference value
Control telegram (slave
⇒
master status word) Present output
frequency
Table 3.30 Process Words (PCD)
3.9.8 FC Protocol Examples
3.9.8.1 Writing a Parameter Value
Change parameter 4-14 Motor Speed High Limit [Hz] to 100
Hz.
Write the data in EEPROM.
PKE=E19E hex - Write single word in parameter 4-14 Motor
Speed High Limit [Hz] .
IND=0000 hex
PWEHIGH=0000 hex
PWELOW=03E8 hex - Data value 1000, corresponding to
100 Hz, see
chapter 3.9.7.12 Conversion .
The telegram looks like this:
E19E H
PKE IND PWE
high
PWE
low
0000 H 0000 H 03E8 H
130BA092.10
Illustration 3.52 Write Data in EEPROM
NOTICE
Parameter 4-14 Motor Speed High Limit [Hz] is a single
word, and the parameter command for write in EEPROM
is E. Parameter number
4-14 is 19E in hexadecimal.
The response from the slave to the master is:
119E H
PKE IND
PWE
high
PWE
low
0000 H 0000 H 03E8 H
130BA093.10
Illustration 3.53 Response from Slave
3.9.8.2 Reading a Parameter Value
Read the value in parameter 3-41 Ramp 1 Ramp Up Time .
PKE=1155 hex - Read parameter value in
parameter 3-41 Ramp 1 Ramp Up Time .
IND=0000 hex
PWEHIGH=0000 hex
PWELOW=0000 hex
System Integration Design Guide
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