Operating instructions

VLT
®
2800, VLT
®
6000 HVAC and VLT
®
8000 AQUA Modbus RTU
■ VLT 2800 Parameter Settings for Modbus
Communication
Using the Modbus RTU Protocol requires setting
of the below listed parameters.
NB!:
Please make sure that par. 512 Telegram
Profile is set to FC PROFILE.
See the VLT 2800 Operating Instructions
MG.28.AX.YY for details on selecting and changing
parameter values, if necessary.
500 Address
(BUS ADDRESS)
Value:
Parameter 500 Protocol = FC protocol [0]
0 - 247
✭ 1
Parameter 500 Protocol = Metasys N2 [1]
1 - 255
✭ 1
Parameter 500 Protocol = MODBUS RTU [3]
1 - 247
✭ 1
Function:
This parameter allows the allocation of an
address to each frequency converter in a serial
communication network.
Description of choice:
The individual frequency converter must be
allocated a unique address.
If the number of units connected (frequency converters
+ master) is higher than 31, a repeater must be used.
Parameter 500 Address cannot be selected via the serial
communication, but must be preset via the control unit.
501 Baudrate
(BAUDRATE)
Value:
300 Baud (300 BAUD)
[0]
600 Baud (600 BAUD)
[1]
1200 Baud (1200 BAUD)
[2]
2400 Baud (2400 BAUD)
[3]
4800 Baud (4800 BAUD)
[4]
✭9600 Baud (9600 BAUD)
[5]
Function:
This parameter is for programming the speed at which
data is transmitted via the serial port. Baud rate is
defined as the number of bits transmitted per second.
Description of choice:
The frequency converter’s transmission speed
must be set at a value corresponding to the
transmission speed of the master.
Parameter 501 Baudrate cannot be selected via the
serial port, but must be preset via the operating unit.
561 Protocol
(PROTOCOL)
Value:
✭FC protocol (FC PROTOCOL)
[1]
Metasys N2 (METASYS N2)
[2]
MODBUS RTU (MODBUS RTU)
[3]
Function:
There is a choice of three different protocols.
Description of choice:
Select the required control word protocol.
570 Modbus parity and message framing
(M.BUS PAR./FRAME)
Value:
(EVEN/1 STOPBIT)
[0]
(ODD/1 STOPBIT)
[1]
✭ (NO PARITY/1 STOPBIT)
[2]
(NO PARITY/2 STOPBIT)
[3]
Function:
This parameter sets up the drive’sModbusRTU
interface to communicate properly with the master
controller. The parity (EVEN, ODD, or NO PARITY) must
be set to match the setting of the master controller.
Description of choice:
Select the parity that matches the setting for the
Modbus master controller. Even or odd parity is
sometimes used to allow a transmitted word to be
checked for errors. Because Modbus RTU uses
the more efficient CRC (Cyclic Redundancy Check)
method of checking for errors, parity checking is
seldom used in Modbus RTU networks.
✭ = factory setting. () = display text [] = value for use in communication via serial communication port
MG.10.S2.02 - VLT is a registered Danfoss trademark
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