Wiring For Modbus Protocol Communication; D. Rs-485 Communication Interface - TECO speecon 7200ma Instruction Manual

D. RS-485 Communication Interface

• 7200MA RS-485 interface (terminal S(+), S(-)) can provide MODBUS protocol
for communication. The PROFIBUS protocol for communication is possible if the
user adopt the PROFIBUS option card (MA-SP).
• Wiring diagram of MODBUS and PROFIBUS-DP:
(a) MODBUS protocol communication
7200 MA
S(+)
S(-)
E
7200 MA
S(+)
S(-)
E
7200 MA
S(+)
S(-)
E
Note :1. A Host Controller with RS-485 interface can communicate with the
7200MA unit through RS-485 interface connection directly. If the Host
Controller does not provide the RS-485 port and its RS-232 port is available,
an RS-485/RS-232 conversion card should be used to connect between this
Host Controller and 7200MA unit.
2. A MODBUS Host Controller can drive the network with no more than 31
drivers connected, using MODBUS communication standard. If the driver
(e.g., 7200MA drive) is at the end of the network, it must have the
terminating resistors 220Ω at both terminals. All other drives in the system
should not have terminators.
3. Please refer to "7200MA RS-485 MODBUS Communication Application
Manual".
M1
P
M2
P
M31
220Ω
P
Fig. 51 Wiring for MODBUS Protocol communication
220Ω
Tx
DATA(+)
Rx
DATA(-)
RS-485/RS-232
conversion CKT
113
RS-485
CONTROLLER
Rx
RS-232
Tx
CONTROLLER