7.4.11 Data Types Supported by the Frequency Converter
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
Unsigned means that there is no operational sign in the telegram.
7.4.12 Conversion
The various attributes of each parameter are displayed in the section
Factory Settings. Parameter values are transferred as whole numbers
only. Conversion factors are therefore used to transfer decimals.
Par. 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 thus perceived as 10.0.
Conversion table
Conversion index
Conversion factor
74
0.1
2
100
1
10
0
1
-1
0.1
-2
0.01
-3
0.001
-4
0.0001
-5
0.00001
7.4.13 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 outp. frequency
7 RS-485 Installation and Set-up
VLT
®
HVAC Drive Design Guide
136
MG.11.B9.02 - VLT
®
is a registered Danfoss trademark
7