3.8.7.7 The PKE Field
The PKE eld contains two subelds:
•
Parameter command and response AK.
•
Parameter number PNU.
15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
130BA268.11
PKE IND
PWE
high
PWE
low
AK PNU
Parameter
commands
and replies
Parameter
number
Figure 3.50 PKE Field
Bits number 12-15 transfer parameter commands from
master to slave and return processed slave responses to
the master.
Bit number Parameter command
15 14 13 12
0 0 0 0 No command
0 0 0 1 Read parameter value
0 0 1 0 Write parameter value in RAM (word)
0 0 1 1 Write parameter value in RAM (double
word)
1 1 0 1 Write parameter value in RAM and
EEPROM (double word)
1 1 1 0 Write parameter value in RAM and
EEPROM (word)
1 1 1 1 Read/write text
Table 3.28 Parameter Commands Master⇒Slave
Bit number Response
15 14 13 12
0 0 0 0 No response
0 0 0 1 Parameter value transferred (word)
0 0 1 0 Parameter value transferred (double
word)
0 1 1 1 Command cannot be performed
1 1 1 1 text transferred
Table 3.29 Response Slave⇒Master
If the command cannot be performed, the slave sends this
response:
0111 Command cannot be performed
- and issues a fault report (see Table 3.30) in the parameter
value (PWE):
PWE low
(hex)
Fault report
0 The parameter number used does not exit.
1 There is no write access to the dened 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 dened
parameter.
11 Data change in the dened parameter is not
possible in the adjustable frequency drive's
present mode. Certain parameters can only be
changed when the motor is turned o.
82 There is no bus access to the dened parameter.
83 Data change is not possible because factory set-up
is selected
Table 3.30 Parameter Value Fault Report
3.8.7.8
Parameter Number (PNU)
Bits number 0-11 transfer parameter numbers. The function
of the relevant parameter is dened in the parameter
description in the Programming Guide.
3.8.7.9
Index (IND)
The index is used together with the parameter number to
read/write-access parameters with an index, e.g.,
15-30 Alarm Log: Error Code. The index consists of two
bytes, a low byte and a high byte.
Only the low byte is used as an index.
3.8.7.10
Parameter Value (PWE)
The parameter value block consists of two words (four
bytes), and the value depends on the dened 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
does not contain a numerical value, but several data
options, e.g., 0-01 Language where [0] is English, and [4] is
Danish, select the data value by entering the value in the
System Integration
Design Guide
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