Mitsubishi FR-A800

(N) Operation via communication and its settings
560
PARAMETERS
5.15.3 Initial setting of operation via communication
 If in communication by the communication option, E.OP1 is displayed.
Setting the communication protocol (Pr.549)
• Select the communication protocol.
• The Modbus-RTU protocol can be used by communication from the RS-485 terminals.
Communication EEPROM write selection (Pr.342)
• When parameter write is performed via the inverter PU connector, RS-485 terminal, USB communication, or a
communication option, the parameters storage device can be changed from EEPROM + RAM to RAM only. Use this
function if parameter settings are changed frequently.
• When changing the parameter values frequently, set "1" in Pr.342 Communication EEPROM write selection to write
them to the RAM only. The life of the EEPROM will be shorter if parameter write is performed frequently with the setting
unchanged from "0 (initial value)" (EEPROM write).
NOTE
• Turning OFF the inverter's power supply clears the modified parameter settings when Pr.342 = "1 (write only to RAM)".
Therefore, the parameter values at next power-ON are the values last stored in EEPROM.
• The parameter setting written in RAM cannot be checked on the operation panel. (The values displayed on the operation
panel are the ones stored in EEPROM.)
Set the action when the inverter is performing operation via communication.
• Set the communication protocol. (Mitsubishi inverter protocol/Modbus-RTU protocol)
• Set the action at fault occurrence or at writing of parameters
Pr. Name
Initial
value
Setting
range
Description
549
N000
Protocol selection
0
0 Mitsubishi inverter protocol (computer link)
1 Modbus-RTU protocol
342
N001
Communication
EEPROM write selection
0
0
Parameter values written by communication are written to
the EEPROM and RAM.
1
Parameter values written by communication are written to
the RAM.
502
N013
Stop mode selection at
communication error
0
0
At fault occurrence At fault removal
Coasts to stop
E.SER display

ALM signal output
Stays stopped (E.SER
display
)
1
Deceleration stop
E.SER display after stop

ALM signal output after stop
Stays stopped (E.SER
display
)
2
Deceleration stop
E.SER display after stop

Automatic restart function
3
Operation continued at the
set frequency of Pr.779
Normal operation
779
N014
Operation frequency
during communication
error
9999
0 to 590 Hz
Set the frequency to be run at a communication error
occurrence.
9999
The motor runs at the frequency used before the
communication error.
Pr.549 setting Communication protocol
0 (initial value) Mitsubishi inverter protocol (computer link)
1 Modbus-RTU protocol