7�- Rs-485 Communications; 7�1�- Connections - Circutor Line-CVM-D32 Instruction Manual

line-CVM-D32
7.- RS-485 COMMUNICATIONS
The line-CVM-D32 devices have RS-485 communications with MODBUS RTU ® communications
protocol.
7�1�- CONNECTIONS
The RS-485 cable must be a twisted pair cable with shielding mesh (minimum 3 wires), and maximum
distance between the line-CVM-D32 device and the master unit must not exceed 12m. in length.
A maximum of 32 line-CVM-D32 devices can be connected to the bus.
For communication with the master unit, a smart RS-232 to RS-485 network protocol converter must
be used.
PC
RS-232 / USB / Ethernet / Profibus ...
RS-232
USB
Ethernet
Profibus
...
RS-485
RS-485
S
B(-)
Note: Default values of the RS-485 communication: 19200 bps, No parity, 8 data bits and 1 stop bit.
Instruction Manual
A(+)
Figure 31: RS-485 connection diagram�
A(+)
24
S
23
B(-)
22
A(+)
A
23 S
22 B(-)
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