Startup; Modbus Rtu Initial Communication Setting - Mitsubishi Electric MR-JE-C Series Instruction Manual

4. Modbus RTU

4.9 STARTUP

This chapter describes the network setting of the MR-JE-_C servo amplifier. Refer to "MR-JE-_C Servo
Amplifier Instruction Manual", "MR-JE-_C Servo Amplifier Instruction Manual (Profile Mode)", and "MR-JE-
_C Servo Amplifier Instruction Manual (Positioning Mode)" for other startup settings.

4.9.1 Modbus RTU initial communication setting

Make the initial communication settings in the following procedure.
Communication function
selection setting
Slave address setting
Baud rate setting
Communication endian setting
Parity setting
Slave (servo amplifier)
power cycling
Modbus RTU communication start
in the master station (controller)
POINT
When using Modbus RTU communication, set [Pr. PF46 Modbus RTU
communication time-out selection] before driving the servo motor. The servo
motor may continue to operate after the communication is disabled due to a
communication shut-off or other causes.
Setting [Pr. PF46 Modbus RTU communication time-out selection] to a small
value may trigger [AL. 8A.2 Modbus RTU communication time-out] in the
following condition: the power of the servo amplifier is cycled, or an
instantaneous power failure occurs during Modbus RTU communication.
[Communication function selection setting]
The initial setting is Ethernet communication. Set the communication function to be used
for the RS-485 communication with the following parameter. (Refer to chapter 5.)
Parameter ("Communication function selection" of [Pr. PN08 Function selection N-2])
[Slave address setting]
The initial value is 0. To change the initial value, set it with either of the following (1) or
(2). (Refer to section 4.9.2.)
(1) Identification number setting rotary switch (SW1/SW2)
(2) Parameter ([Pr. PC70 Modbus RTU communication station number setting])
[Baud rate setting]
The initial value is 115200 [bps]. To change the initial value, set it with the following
parameter. (Refer to chapter 5.)
Parameter ("Modbus RTU communication baud rate selection" of [Pr. PC71 Function
selection C-F])
[Communication endian setting]
The initial value is standard endian (little-endian). To change the initial value, set it with
the following parameter. (Refer to chapter 5.)
Parameter ("Modbus RTU communication endian selection" of [Pr. PC72 Function
selection C-G])
[Parity setting]
The initial value is even parity and stop bit length of 1 bit. To change the initial value, set
it with the following parameter. (Refer to chapter 5.)
Parameter ("Protocol parity selection" of [Pr. PF45 Function selection F-12])
[Slave (servo amplifier) power cycling]
The slave address, baud rate, communication endian, and parity are reflected.
[Communication start]
Start Modbus RTU communication of the master (controller).
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