7
VLT is a registered Danfoss trade mark
MG.10.P2.22
Modbus
RTU Option
Card Baud
Rate and
Parity
Settings
The Modbus communication protocol accesses
the internal VLT Danfoss FC protocol to control
the drive through serial communications. The
Modbus-to-FC interface uses 9600 Baud, 8
Bits, Even Parity, 1 Stop Bit.
The Modbus option card has a baud rate and
parity 8-input dip switch. For Modbus
networks operating with Modbus-to-FC
properties, set switch positions in accordance
with the following instructions. For Modbus
networks operating at other than with
Modbus-to-FC properties, determine switch
positions from the tables provided below.
Baud Rate and Parity Switch
• Ensure that inputs 1-3 are set to ON (default
setting) to select the 9600 baud rate.
• Ensure that inputs 4 and 5 are set to ON
(default setting) to select even parity.
Switches 6-8 are unassigned reserved
switches. Their setting does not matter.
NOTE
Set baud rate and parity switch
settings prior to installing Modbus
RTU option card for ease of
access.
2
1
3
4
5
6
7
8
ON
ON
OFF
Baud
Rate
SW1
SW2
SW3
Parity
SW4
SW5
300
OFF
OFF
OFF
N
ON
X
1200
OFF
OFF
ON
O
OFF
ON
2400
OFF
ON
OFF
E
OFF
OFF
4800
OFF
ON
ON
9600
ON
OFF
OFF
19200
ON
OFF
ON
9600
ON
ON
OFF
9600
ON
ON
ON
Communication
Baud Rate
Parity
Reserved
Configuration
SW1
SW2
SW3
SW4
SW5
SW6
SW7
SW8
Default
9600, 8N
ON
ON
ON
ON
ON
N/A
N/A
N/A
4800, 8O
OFF
ON
ON
OFF
ON
N/A
N/A
N/A
19200, 8E
ON
OFF
ON
OFF
OFF
N/A
N/A
N/A
