Fc Protocol Examples - Danfoss VLT AQUA Drive FC 202 Design Manual

System Integration
PWE block. Serial communication is only capable of
reading parameters containing data type 9 (text string).
15-40 FC Type to 15-53 Power Card Serial Number contain
data type 9.
3 3
For example, read the unit size and AC line voltage range
in 15-40 FC Type. When a text string is transferred (read),
the length of the message is variable, and the texts are of
different lengths. The message length is defined in the
second byte of the message, 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 serial bus. To write a text via the PWE block, set the
parameter command (AK) to F hex. The index characters
high-byte must be 5.
Figure 3.51 Text via PWE Block
3.8.7.11 Supported Data Types
Unsigned means that there is no operational sign in the
message.
Data types
3
4
5
6
7
9
10
13
33
35
Table 3.31 Supported Data Types
3.8.7.12 Conversion
The various attributes of each parameter are displayed in
factory setting. Parameter values are transferred as whole
numbers only. Conversion factors are therefore used to
transfer decimals.
4-12 Motor Speed Low Limit [Hz] has a conversion factor of
0.1. To preset the minimum frequency to 10 Hz, transfer
86
PKE IND PWE
high
Read text Fx xx 04 00
Write text Fx xx 05 00
Description
Integer 16
Integer 32
Unsigned 8
Unsigned 16
Unsigned 32
Text string
Byte string
Time difference
Reserved
Bit sequence
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VLT AQUA Drive FC 202
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
3.8.7.13 Process Words (PCD)
The block of process words is divided into two blocks of
16 bits, which always occur in the defined sequence.
PCD 1
Control message (master⇒slave control word) Reference value
Control message (slave⇒master) status word
Table 3.32 Process Words (PCD)
PWE
low

3.8.8 FC Protocol Examples

3.8.8.1 Writing a Parameter Value
Change 4-14 Motor Speed High Limit [Hz] to 100 Hz.
Write the data in EEPROM.
PKE=E19E hex - Write single word in 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 3.8.7.12 Conversion.
The message looks like this:
E19E
PKE
Figure 3.52 Write Data in EEPROM
NOTICE!
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.
H 0000 H 0000 H 03E8
IND PWE
high
PCD 2
Present output
frequency
H
PWE
low
MG20N622