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15-40 FC Type
to
15-53 Power Card Serial Number
contain
data type 9.
For example, read the unit size and mains voltage range in
15-40 FC Type
. When a text string is transferred (read), the
length of the telegram is variable, and the texts 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 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”.
Illustration 7.11
7.3.11 Data Types Supported by the
Frequency Converter
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 7.8
7.3.12 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
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:
0s
⇒
conversion index 0
0.00s
⇒
conversion index -2
0ms
⇒
conversion index -3
0.00ms
⇒
conversion index -5
Conversion index
Conversion factor
100
75
74
67
6
1000000
5
100000
4
10000
3
1000
2
100
1
10
0
1
-1
0.1
-2
0.01
-3
0.001
-4
0.0001
-5
0.00001
-6
0.000001
-7
0.0000001
Table 7.9 Conversion Table
7.3.13 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
PCD 2
Control telegram (master
⇒
slave Control
word)
Reference-value
Control telegram (slave
⇒
master) Status
word
Present output
frequency
Table 7.10
7.4 Examples
7.4.1 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]
RS-485 Installation and Set...
VLT
®
Refrigeration Drive Design Guide
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