Network Connection; Frequency Converter Hardware Set-Up; Parameter Settings For Modbus Communication - Danfoss VLT Compressor Drive CDS 803 Design Manual

RS485 Installation and Set-...

7.1.2 Network Connection

Connect the frequency converter to the RS485 network
as follows (see also Illustration 7.2):
1. Connect signal wires to terminal 68 (P+) and
terminal 69 (N-) on the main control board of the
frequency converter.
2. Connect the cable shield to the cable clamps.
NOTICE
To reduce noise between conductors, use shielded,
twisted-pair cables
7 7
Illustration 7.2 Network Connection

7.1.3 Frequency Converter Hardware Set-up

Use the terminator dip switch on the main control board
of the frequency converter to terminate the RS485 bus.
The factory setting for the dip switch is OFF.
50
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VLT Compressor Drive CDS 803
61 68 69
Danfoss A/S © 12/2015 All rights reserved.
7.1.4 Parameter Settings for Modbus
Communication
Parameter Function
Parameter 8-30 Prot Select the application protocol to run for
ocol the RS485 interface.
Parameter 8-31 Add Set the node address.
NOTICE
ress
The address range depends on the
protocol selected in
parameter 8-30 Protocol.
Parameter 8-32 Bau Set the baud rate.
NOTICE
d Rate
The default baud rate depends on the
protocol selected in
parameter 8-30 Protocol.
Parameter 8-33 Pari Set the parity and number of stop bits.
NOTICE
ty / Stop Bits
The default selection depends on the
protocol selected in
parameter 8-30 Protocol.
Parameter 8-35 Min Specify a minimum delay time between
imum Response receiving a request and transmitting a
Delay response. This function is for overcoming
modem turnaround delays.
Parameter 8-36 Ma Specify a maximum delay time between
ximum Response transmitting a request and receiving a
Delay response.
Parameter 8-37 Ma If transmission is interrupted, specify a
ximum Inter-char maximum delay time between 2 received
delay bytes to ensure timeout.
NOTICE
The default selection depends on the
protocol selected in
parameter 8-30 Protocol.
Table 7.2 Modbus Communication Parameter Settings
MG18N202