Danfoss VLT AutomationDrive FC 301 Series Design Manual page 197

RS-485 Installation and Set...
Conversion index
100
75
74
67
6
5
4
3
2
1
0
-1
-2
-3
-4
-5
-6
-7
Table 12.8 Conversion Table
12.7.13 Process Words (PCD)
The block of process words is divided into two blocks of
16 bits, which always occur in the defined sequence.
PCD 1
Control message (master⇒follower control
word)
Control message (follower⇒master) status
word
Table 12.9 Process Words (PCD)
12.8 Examples
12.8.1 Writing a Parameter Value
Change 4-14 Motor Speed High Limit [Hz] to 100 Hz.
Write the data in EEPROM.
PKE = E19E Hex - Write single word in 4-14 Motor Speed
High Limit [Hz]
IND = 0000 Hex
PWEHIGH = 0000 Hex
PWELOW = 03E8 Hex - Data value 1000, corresponding to
100 Hz, see chapter 12.7.12 Conversion.
MG33BF22
Design Guide
Conversion factor
1000000
100000
10000
1000
100
10
1
0.1
0.01
0.001
0.0001
0.00001
0.000001
0.0000001
PCD 2
Reference value
Present output
frequency
Rev. 2014-04-04 All rights reserved.
The message looks like this:
E19E H 0000 H 0000
PKE IND PWE
Figure 12.12 Write Data in EEPROM
NOTICE!
4-14 Motor Speed High Limit [Hz] is a single word, and the
parameter command for write in EEPROM is "E".
Parameter number 4-14 is 19E in hexadecimal.
The response from the follower to the master is:
119E H 0000 H 0000
PWE
IND
PKE
Figure 12.13 Response from Follower
12.8.2 Reading a Parameter Value
Read the value in 3-41 Ramp 1 Ramp-up Time
PKE = 1155 Hex - Read parameter value in 3-41 Ramp 1
Ramp-up Time
IND = 0000 Hex
PWEHIGH = 0000 Hex
PWELOW = 0000 Hex
1155 H 0000 H 0000
PKE IND
Figure 12.14 Parameter Value
If the value in 3-41 Ramp 1 Ramp-up Time is 10 s, the
response from the follower to the master is
Figure 12.15 Response from Follower
3E8 Hex corresponds to 1000 decimal. The conversion
index for 3-41 Ramp 1 Ramp-up Time is -2, i.e., 0.01.
3-41 Ramp 1 Ramp-up Time is of the type Unsigned 32.
H 03E8 H
PWE
high low
H 03E8 H
PWE
high low
H 0000 H
PWE PWE
high low
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