Danfoss VLT Series Design Manual page 143

VLT ® HVAC Drive Design Guide
PWE low (Hex) Fault Report
7.4.8. Parameter Number (PNU)
Bits no. 0-10 transfer parameter numbers. The function of the relevant parameter is defined in
the parameter description in the chapter entitled
7.4.9. Index (IND)
The index is used together with the parameter number to read/write-access parameters with an
index, e.g., par. 15-30
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), 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 not a numerical
value but several data options, such as par. 0-01 Language where [0] corresponds to English, and
[4] corresponds to Danish, select the data value by entering the value in the PWE block. See
Example - Selecting a data value. Serial communication is only capable of reading parameters
containing data type 9 (text string).
Parameters 15-40 to 15-53 contain data type 9.
For example, read the unit size and line voltage range in par. 15-40
is transferred (read), the length of the telegram is variable, and the texts are of different lengths.
The message 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.
0 The parameter number used does not exit.
1 There is no write access to the defined parameter.
2 Data value exceeds the parameter's limits.
3 The sub index used does not exit.
4 The parameter is not the array type.
5 The data type does not match the defined parameter.
11 Data change in the defined parameter is not possible in the adjustable
frequency drive's present mode. Certain parameters can only be changed
when the motor is turned off.
82 There is no bus access to the defined parameter.
83 Data change is not possible because the factory set-up is selected
Error Code
. The index consists of 2 bytes, a low byte and a high byte.
NOTE
Only the low byte is used as an index.
MG.11.B4.22 - VLT ® is a registered Danfoss trademark.
7. RS-485 Installation and Set-up
How to Program
.
FC Type
. When a text string
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