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MG.90.D1.02 – VLT is a registered Danfoss trademark
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VLT
®
5000/5000 Flux/6000 HVAC/8000 AQUA PROFIBUS
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Parameters and data type structures
Parameter description
Parameters which are accessible through the pa-
rameter number (PNU) have additional attributes
that are a component of the accompanying de-
scriptive element.
Writing/reading of a parameter description occurs
through the PCV portion by means of the RC
commands 4/5 and the subindex of the desired
descriptive element (see accompanying diagram).
Characteristics
The “characteristics” subindex extends the defini-
tion of the parameter description. The individual
bits 9 to 15 have the values TRUE [1] or FALSE [0]
(see table below).
Bit
Meaning
15
Active parameter
14
Array
13
Parameter value resettable only
12
Factory setting of parameter changed
11
Text available
10
Additional text array available
9
No write access (read only)
8
Lower and upper limit. Standardiza-
tion and size attribute not relevant.
0-7
Data type of the parameter corre-
sponds to OD
The low byte (bit 0-7) indicates the data type of
the parameter (see following table).
The ”data type” for each parameter can be
found in the corresponding column in the
chapter parameter listing.
PNU
Caracteristics
"Sub index" 1
Element size
"Sub index" 2
Size attribute
"Sub index" 4
Lower limit
"Sub index" 7
Upper limit
"Sub index" 8
Extended features
"Sub index" 10
Data types supported by VLT
Data
Object
Short
Description
type
form
3
5
12
Integer 16
4
5
12
Integer 32
5
5
Unsigned 8
6
5
O2
Unsigned 16
7
5
O4
Unsigned 32
9
5
Visible string
10
5
Byte string
13
5
Time difference
1)
33
5
N2
Standardized value
(16 bit)
1)
35
5
V2
Bit sequence
1)
See following page for details
Example: Data type 5 = Unsigned 8
Size attribute
The size attribute is 2 bytes long.
Byte 1 incorporates the physical unit of measure-
ment (size index), byte 2 the conversion index.
The
”conversion index”
for each parameter
can be found in the corresponding column
in the chapter parameter listing.
The ”conversion index” produces the conversion
factor for each parameter.
Example:
Parameter 205: Conversion index = -3 <=> (10E-3)
Conversion factor: 0.001
15200 = 15.200 Hz
An excerpt from the PROFIDRIVE profile with
respect to the assignment of the size index and
the conversion index to the physical size can be
found on the following page.
Parameters and data type structures