Conversion index
Conversion factor
74
3600
2
100
1
10
0
1
-1
0.1
-2
0.01
-3
0.001
-4
0.0001
-5
0.00001
Table 5.9 Conversion
5.4.13 Process Words (PCD)
The block of process words is divided into 2 blocks of 16
bits, which always occur in the defined sequence.
PCD 1
PCD 2
Control telegram (master
⇒
slave control word) Reference value
Control telegram (slave
⇒
master) status word Present output
frequency
Table 5.10 Process Words (PCD)
5.5 Examples
5.5.1 Writing a Parameter Value
Change
parameter 4-14 Motor Speed High Limit [Hz]
to 100
Hz.
Write the data in EEPROM.
PKE = E19E hex - Write single word in
parameter 4-14 Motor Speed High Limit [Hz]
:
•
IND = 0000 hex.
•
PWEHIGH = 0000 hex.
•
PWELOW = 03E8 hex.
Data value 1000, corresponding to 100 Hz, see
.
The telegram looks like
E19E H
PKE
IND
PWE
high
PWE
low
0000 H 0000 H 03E8 H
130BA092.10
Illustration 5.9 Telegram
NOTICE
Parameter 4-14 Motor Speed High Limit [Hz]
is a single
word, and the parameter command for write in EEPROM
is
E
.
Parameter 4-14 Motor Speed High Limit [Hz]
is 19E in
hexadecimal.
The response from the slave to the master is shown in
119E H
PKE
IND
PWE
high
PWE
low
0000 H 0000 H 03E8 H
130BA093.10
Illustration 5.10 Response from Master
5.5.2 Reading a Parameter Value
Read the value in
parameter 3-41 Ramp 1 Ramp Up Time
.
PKE = 1155 hex - Read parameter value in
parameter 3-41 Ramp 1 Ramp Up Time
:
•
IND = 0000 hex.
•
PWE
HIGH
= 0000 hex.
•
PWE
LOW
= 0000 hex.
1155 H
PKE
IND
PWE
high
PWE
low
0000 H 0000 H 0000 H
130BA094.10
Illustration 5.11 Telegram
If the value in
parameter 3-41 Ramp 1 Ramp Up Time
is 10
s, the response from the slave to the master is shown in
130BA267.10
1155 H
PKE
IND
0000 H 0000 H 03E8 H
PWE
high
PWE
low
Illustration 5.12 Response
3E8 hex corresponds to 1000 decimal. The conversion
index for
parameter 3-41 Ramp 1 Ramp Up Time
is -2, that
is, 0.01.
Parameter 3-41 Ramp 1 Ramp Up Time
is of the type
Unsigned 32
.
RS485 Installation and Set-...
Design Guide
MG07B102
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