the function code read holding register or write multiple
registers in 1 telegram. The structure is also flexible so that
only 2 registers can be written to, and 10 registers can be
read from the controller.
The PCD write list is data sent from the controller to the
frequency converter such as:
•
Control word.
•
Reference.
•
Application dependent data like minimum
reference and ramp times.
NOTICE
The control word and reference is always sent in the list
from the controller to the frequency converter.
The PCD write list is set up in
parameter 8-42 PCD Write
Configuration
.
The PCD read list is data sent from the frequency converter
to the controller such as:
•
Status word.
•
Main actual value.
•
Application-dependent data like running hours,
motor current, and alarm word.
NOTICE
The status word and main actual value are always sent in
the list from the frequency converter to the controller.
CTW
Holding
Register
2810
Write
Master Frequency Converter
Read
Frequency
Converter Master
Controlled by
Parameter
Holding
Register
Controlled by
Parameter
8-42 [0]
REF
2811
8-42 [1]
2812
8-42 [2]
PCD 2
write
2813
8-42 [3]
PCD 3
write
2814
8-42 [4]
PCD 4
write
2815
8-42 [5]
PCD 5
write
...
...
...
write
2873
8-42 [63]
PCD 63
write
STW
2910
8-43 [0]
MAV
2911
8-43 [1]
2912
8-43 [2]
PCD 2
read
2913
8-43 [3]
PCD 3
read
2914
8-43 [4]
PCD 4
read
2915
8-43 [5]
PCD 5
read
...
...
...
read
2919
8-43 [63]
PCD 63
read
130BC048.10
Illustration 3.15 PCD Write/Read Lists
NOTICE
The boxes marked in gray are not changeable, they are
the default values.
NOTICE
Map 32-bit parameters inside the 32-bit boundaries,
PCD2 & PCD3 or PCD4 & PCD5, and so on, where the
parameter number is mapped twice to
parameter 8-42 PCD Write Configuration
or
parameter 8-43 PCD Read Configuration
.
3.8.10 Mapping the Holding Registers to
Drive Parameters
Example:
The PLC sends control word, reference, set the analog
output 42 and set the torque limit.
CTW
REF
Analog
output 42
Torque
limit
Register 2810
2811
2812
2813
Write
Frequency Converter Drive
CTW = Parameter 16-85,
Analog output = Parameter 6-52,
REF = Parameter 16-86,
Torque limit Motor mode = 4-16
130BC049.10
Illustration 3.16 PLC Sending Data
Example:
The frequency converter sends status word, main actual
value, actual motor current, digital inputs, and torque
[Nm].
Motor
current
Digital
inputs
Actual
Torque [Nm]
Register 2910
2911
2912
2913
2914
Read
Frequency Converter Master
STW
MAV
130BC050.10
STW = Parameter 16-03,
Motor Current = Parameter 16-14,
Actual Torque [Nm]
MAV = Parameter 16-05,
Digital Inputs = Parameter 16-60
Illustration 3.17 Frequency Converter Sending Data
Example, continued
Map the input and output data of the Modbus RTU to the
parameter of the frequency converter. Use
parameter 8-42 PCD Write Configuration
and
parameter 8-43 PCD Read Configuration
for the mapping.
RS485 Installation and Set-...
VLT
®
DriveMotor FCP 106/FCM 106
26
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MG03N202
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