Mitsubishi Electric F700 User Manual

189
Communication operation and setting
4
PARAMETERS
4.19.6 Modbus-RTU communication specifications
(Pr. 331, Pr. 332, Pr. 334, Pr. 343, Pr. 539, Pr. 549)
(1) Communication specifications
⋅ The communication specifications are given below.
Using the Modbus-RTU communication protocol, communication operation or parameter setting can be
performed from the RS-485 terminals of the inverter.
Parameter
Number
Name
Initial
Value
Setting Range Description
331
RS-485
communication
station number
0
0 Broadcast communication is selected.
1 to 247
Specify the inverter station number.
Set the inverter station numbers when two or more
inverters are connected to one personal computer.
332
RS-485
communication
speed
96
3, 6, 12, 24, 48,
96, 192, 384
Set the communication speed.
The setting value × 100 equals the communication speed.
For example, the communication speed is 9600bps when
the setting value is "96".
334
RS-485
communication parity
check selection
2
0
Without parity check
Stop bit length 2bits
1
With odd parity check
Stop bit length 1bit
2
With even parity check
Stop bit length 1bit
343
Communication error
count
0 
Display the number of communication errors during
Modbus-RTU communication. Reading only
539
Modbus-RTU
communication check
time interval
9999
0
Modbus-RTU communication can be made, but the inverter
will come to an alarm stop in the NET operation mode.
0.1 to 999.8s
Set the interval of communication check time.
(same specifications as Pr. 122)
9999 No communication check (signal loss detection)
549 Protocol selection 0
0 Mitsubishi inverter (computer link) protocol
1 Modbus-RTU protocol
The above parameters can be set when Pr. 160 User group read selection = "0". (Refer to page 156)
CAUTION
When Modbus-RTU communication is performed from the master with address 0 (station 0) set, broadcast communication is
selected and the inverter does not send a response message to the master.
When response from the inverter is necessary, set a value other than "0" in Pr. 331.
Some functions are invalid for broadcast communication. (Refer to page 191.)
REMARKS
⋅ When using the Modbus-RTU protocol, set Pr. 549 Protocol selection to "1".
⋅ When the communication option is fitted with Pr. 550 NET mode operation command source selection set to "9999" (initial value), the
command source (e.g. run command) from the RS-485 terminals is invalid. (Refer to page 167)
Item Description
Related
Parameters
Communication protocol Modbus-RTU protocol Pr. 549
Conforming standard EIA-485 (RS-485)

Number of inverters connected 1: N (maximum 32 units), setting is 0 to 247 stations Pr. 331
Communication speed Can be selected from 300, 600, 1200, 2400, 4800, 9600, 19200 and 38400bps Pr. 332
Control protocol Asynchronous system 
Communication method Half-duplex system 
Communication
specifications
Character system Binary(fixed to 8 bits) 
Start bit 1bit 
Stop bit length
Select from the following three types
⋅ No parity, stop bit length 2 bits
⋅ Odd parity, stop bit length 1 bit
⋅ Even parity, stop bit length 1 bit
Pr. 334
Parity check
Error check CRC code check 
Terminator Not used 
Waiting time setting Not used 

Mitsubishi Electric F700 Specifications

General

Brand	Mitsubishi Electric
Model	F700
Category	Inverter
Language	English