Cim 200 Modbus Rtu Setup; Setting The Modbus Transmission Speed - Grundfos CIM 200 Functional Profile And User Manual

5. CIM 200 Modbus RTU setup

1 2 3 4
Fig. 7 CIM 200 Modbus module
Pos. Designation
1 D1
2 D0
3 Common/GND
4 SW1/SW2
5 SW3/SW4/SW5
6 LED1
7 LED2
8 SW6
9 SW7
Use a screened, twisted-pair cable. Connect the cable screen to
protective earth at both ends.
Recommended connection
Modbus terminal Colour code
D1-TXD1 Yellow
D0-TXD0 Brown
Common/GND Grey
8
9
5 6 7
Description
Modbus terminal D1, positive
data signal
Modbus terminal D0, negative
data signal
Modbus terminal
Common and GND
On and off switches for
termination resistor
Switches for selection of Modbus
parity and transmission speed
Red and green status LED for
Modbus communication
Red and green status LED for
internal communication between
CIM 200 and the Grundfos
product
Hexadecimal rotary switch for
setting the Modbus address, four
most significant bits
Hexadecimal rotary switch for
setting the Modbus address, four
least significant bits
Data signal
Positive
Negative
Common/GND

5.1 Setting the Modbus transmission speed

Set the transmission speed correctly before CIM 200 is ready to
communicate with the Modbus network. Use DIP switches SW4
and SW5 for setting the transmission speed. See fig. 8.
SW4 SW5
Fig. 8 Modbus transmission speed
DIP switch settings
Available transmission speeds in bits/s: 1200, 2400, 4800, 9600,
19200 and 38400.
The first three transmission speeds are only available via
software settings, whereas the last three are available via DIP
switches.
Transmission speed [bits/s]
9600
19200
38400
Software-defined
Default transmission speed is 19200 bits per second, as per the
Modbus RTU standard.
Software-defined
When SW4 and SW5 are set to "software-defined", writing a
value to the holding register at address 00004 will set a new
transmission speed.
Use the following values for software-defined transmission
speeds:
Software-defined transmission
speed
1200 bits/s
2400 bits/s
4800 bits/s
9600 bits/s
19200 bits/s
38400 bits/s
This value is set to 1200 bits/s as default.
The communication interface does not support transmission
speeds above 38400 bits/s.
The software-defined transmission speed value is stored in the
communication interface and remains after a power-off.
When software defined has been selected, then
communication speed, parity bit, stop bits and
address are all set via specific registers. See section
5.2 Setting the stop bits and the parity bit
5.3 Modbus address
SW4 SW5
OFF ON
OFF OFF
ON OFF
ON ON
Value to set in register
00004
0
1
2
3
4
5
and section
selection.
9