Danfoss VLT HVAC Basic Drive FC 101 Design Manual page 82

RS-485 Installation and Set...
If the command cannot be performed, the slave sends this
response:
0111 Command cannot be performed
- and issues the following fault report in the parameter
value:
Error code
0 Illegal Parameter Number
1 Parameter cannot be changed.
2 Upper or lower limit exceeded
3 Subindex corrupted
4 No Array
5 Wrong Data Type
6 Not used
7 Not used
9 Description element not available
11 No parameter write access
15 No text available
17 Not while Running
18 Other error
100
>100
130 No bus access for this parameter
131 Write to factory set-up not possible
132 No LCP access
252 Unknown viewer
253 Request not supported
254 Unknown attribute
255 No error
Table 7.7
7.4.8 Parameter Number (PNU)
Bits no. 0-11 transfer parameter numbers. The function of
the relevant parameter is defined in the parameter
description in 6 How to Programme.
7.4.9 Index (IND)
The index is used together with the parameter number to
read/write-access parameters with an index, for example,
15-30 Alarm Log: Error Code. The index consists of 2 bytes;
a low byte, and a high byte.
Only the low byte is used as an index.
7.4.10 Parameter Value (PWE)
The parameter value block consists of 2 words (4 bytes),
and the value depends on the defined command (AK). The
master prompts for a parameter value when the PWE block
contains no value. To change a parameter value (write),
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VLT HVAC Basic Drive Design Guide
FC+ Specification
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write the new value in the PWE block and send from the
master to the slave.
When a slave responds to a parameter request (read
command), the present parameter value in the PWE block
is transferred and returned to the master. If a parameter
contains several data options, e.g. 0-01 Language, select
the data value by entering the value in the 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.
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".
7.4.11 Data Types Supported by the
Frequency Converter
Unsigned means that there is no operational sign in the
telegram.
Data types
3
4
5
6
7
9
Table 7.8
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.
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.
Description
Integer 16
Integer 32
Unsigned 8
Unsigned 16
Unsigned 32
Text string
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