The Pke Field; Parameter Number (Pnu); Index (Ind); Parameter Value (Pwe) - Danfoss VLT Compressor Drive CDS 803 Design Manual

RS485 Installation and Set-...

7.4.7 The PKE Field

The PKE field contains 2 subfields:
•
Parameter command and response (AK)
•

Parameter number (PNU)

AK
15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
7 7
Illustration 7.9 PKE Field
Bits 12–15 transfer parameter commands from master to
slave and return processed slave responses to the master.
Parameter commands master⇒slave
Bit number
15 14 13
0 0 0
0 0 0
0 0 1
0 0 1
1 1 0
1 1 1
1 1 1
Table 7.5 Parameter Commands
Response slave⇒master
Bit number
15 14 13
0 0 0
0 0 0
0 0 1
0 1 1
1 1 1
Table 7.6 Response
54
VLT
PKE IND PWE
high
PNU
Parameter command
12
0 No command.
1 Read parameter value.
0 Write parameter value in RAM (word).
1 Write parameter value in RAM (double
word).
1 Write parameter value in RAM and
EEPROM (double word).
0 Write parameter value in RAM and
EEPROM (word).
1 Read text.
Response
12
0 No response.
1 Parameter value transferred (word).
0 Parameter value transferred (double
word).
1 Command cannot be performed.
1 Text transferred.
Danfoss A/S © 12/2015 All rights reserved.
®
Compressor Drive CDS 803
If the command cannot be performed, the slave sends this
response 0111 Command cannot be performed and issues
the following fault report in Table 7.7.
Fault code
0
1
2
PWE
low
3
4
5
6
7
9
11
15
17
18
100
>100
130
131
132
252
253
254
255
Table 7.7 Slave Report
7.4.8 Parameter Number (PNU)
Bit numbers 0–11 transfer parameter numbers. The
function of the relevant parameter is defined in the
parameter description in chapter 6 How to Program.

7.4.9 Index (IND)

The index is used with the parameter number to read/
write access parameters with an index, for example,
parameter 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),
write the new value in the PWE block and send from the
master to the slave.
FC specification
Illegal parameter number.
Parameter cannot be changed.
Upper or lower limit is exceeded.
Subindex is corrupted.
No array.
Wrong data type.
Not used.
Not used.
Description element is not available.
No parameter write access.
No text available.
Not applicable while running.
Other errors.
–
–
No bus access for this parameter.
Write to factory set-up is not possible.
No LCP access.
Unknown viewer.
Request is not supported.
Unknown attribute.
No error.
MG18N202