MCD Modbus Module Instructions
Modbus
Functions
MG.17.F5.02 - VLT
® is a registered Danfoss trademark
7
8.
Modbus Functions
The Modbus Module supports the following Modbus functions:
03 Read multiple registers
06 Write single register
Modbus broadcast functions are not supported.
MCD 200 soft starters (including Remote Operator):
Read multiple registers 40003 to 40008
Write single register 40002
MCD 500 soft starters:
Read multiple registers starting from 40003 up to a maximum of 125 register blocks
Write single register 40002 or 40009 to 40599
N.B.!:
A multiple read across register boundary 40008/40009 will result in a Modbus Error code
05 at the Master.
Modbus Module version 3 and earlier (serial number xxxxxx-3) can read a maximum of
119 register blocks.
8.1.
Master Configuration
For standard Modbus 11-bit transmission, the Master must be configured for 2 stop bits with No
Parity and 1 stop bit for odd or even parity.
For 10-bit transmission, the Master must be configured for 1 stop bit.
In all cases, the Master baud rate and slave address must match those set on the Modbus Module DIP
switches.
Command: Start
Message
Starter
Address
Function Code
Register
Address
Data
CRC
In 20 06 40002 1
CRC1,
CRC2
Out 20 06 40002 1
CRC1,
CRC2
Starter status: Running
Message
Starter
Address
Function Code
Register
Address
Data
CRC
In 20 03 40003 1
CRC1,
CRC2
Out
20
03
2 (bytes)
3
CRC1, CRC2
Trip code: Motor overload
Message
Starter
Address
Function Code
Register
Address
Data
CRC
In 20 03 40004 1
CRC1,
CRC2
Out
20
03
2 (bytes)
2
CRC1, CRC2
Download parameter from starter
MCD 500: Read Parameter 1, Motor FLC (Parameter 1-1), 100 A
Message
Starter
Address
Function
Code
Register
Address
Data
CRC
In 20 03
40009
1
CRC1,
CRC2
Out
20
03
2 (bytes)
100
CRC1, CRC2