Modbus-Rtu Communication Specifications (Pr.117, Pr.118, Pr.120, Pr.122, Pr.343, Pr.502, Pr.549); Modbus-Rtu Communication Specifications - Mitsubishi Electric FR-E700EX Instruction Manual

Communication operation and setting

4.18.6 Modbus-RTU communication specifications

(Pr.117, Pr.118, Pr.120, Pr.122, Pr.343, Pr.502, Pr.549)
Using the Modbus-RTU communication protocol, communication operation or parameter setting can be performed from
the PU connector of the drive unit.
Parameter
Name
number
PU communication
117
station number
118 PU communication speed
PU communication parity
120
check
PU communication check
122
time interval
Communication error
343
count
Stop mode selection at
502
communication error
549 Protocol selection
The above parameters can be set when Pr.160 Extended function display selection = "0". (Refer to page 182)
 When Modbus-RTU communication is performed from the master with address 0 (station number 0) set, broadcast communication is selected and the drive
unit does not send a response message. When response from the drive unit is necessary, set a value other than "0" (initial value is 0) in Pr.117 PU
communication station number.
Some functions are invalid for broadcast communication. (Refer to page 225)
NOTE
 When "1" (Modbus-RTU protocol) is set in Pr.549 and "384" (38400bps) in Pr.118, parameter unit (FR-PU07) is disabled.
When using the parameter unit (FR-PU07), change parameter using the operation panel.
REMARKS
 Set Pr.549 Protocol selection to "1" to use the Modbus-RTU protocol.
 When PU connector is selected as NET mode command source (when Pr.550 NET mode operation command source selection = "2"
or "9999" (initial value) without communication option), Modbus-RTU communication operation can be performed. (Refer to page
195)
222
Initial Setting
value range
No reply to the master 
0
Drive unit station number specification
0
1 to 247 Set the drive unit station numbers when two or more drive units are
connected to one personal computer.
Communication speed
48, 96,
The setting value  100 equals the communication speed.
192
192, 384
Example) 9600bps if 96
Without parity check
0
Stop bit length 2 bits
With odd parity check
2 1
Stop bit length 1 bit
With even parity check
2
Stop bit length 1 bit
RS-485 communication can be made. Note that a communication
0 fault (E.PUE) occurs as soon as the drive unit is switched to the
operation mode with command source.
0 Communication check (signal loss detection) time interval If a no-
0.1 to
communication state persists for longer than the permissible time,
999.8s
the drive unit trips (depends on Pr.502).
9999 No communication check (signal loss detection)
Displays the number of communication errors during Modbus-RTU

0
communication (reading only)
At Fault
Occurrence
0, 3 Coasts to stop.
0
Decelerates to
1
stop
Decelerates to
2
stop
0 Mitsubishi inverter (computer link operation) protocol
0
1 Modbus-RTU protocol
Description
Fault
Indication
Output
E.PUE Output
After stop Output
E.PUE after stop
After stop Without
E.PUE output
At Fault
Removal
Stop
(E.PUE)
Stop
(E.PUE)
Automatic
restart
functions