Parameters related to RS-485 terminal communication
stop bit length
stop bit length / data
parity check selection
check time interval
waiting time setting
When "1" (MODBUS RTU protocol) is set in Pr.549, the setting range within parentheses is applied.
When a value outside the setting range is set, the inverter operates at the initial value.
When Pr.549 = "2" (BACnet MS/TP protocol), the setting range is "96 to 1152".
In the MODBUS RTU protocol, the data length is fixed at 8 bits.
In the MODBUS RTU protocol, Pr.334 setting is applied as the stop bit length. (Refer to
In the MODBUS RTU protocol, this is invalid.
• The monitor items and parameter settings can be read during communication with the Pr.336 RS-485 communication check
time interval = "0 (initial value)" setting, but such operation will become faulty once the operation mode is changed to the NET
operation mode. When the NET operation mode is selected as the start-up operation mode, communication is performed once,
then a Communication fault (inverter) (E.SER) occurs. To perform operation or parameter writing via communication, set
"9999" or a large setting value in Pr.336. (The setting value is determined by the computer program.) (Refer to
• Always reset the inverter after making the initial settings of the parameters. After changing the communication-related
parameters, communication cannot be made until the inverter is reset.
5.12.5 Mitsubishi inverter protocol (computer link
Parameter setting and monitoring, etc. are possible by using the Mitsubishi inverter protocol (computer link communication) via
inverter PU connector and the RS-485 terminals.
5.12 (N) Communication operation parameters
0 to 31 (0 to
3, 6, 12, 24, 48, 96,
192, 384, 576, 768,
0, 1, 10, 11
0, 1, 2
0 to 10, 9999
0.1 to 999.8 s
0 to 150 ms, 9999
0, 1, 2
Enter the station number of the inverter.
(Same specifications as Pr.117)
Select the communication speed.
(Same specifications as Pr.118)
Select the data length. (Same specifications as P.E022)
Select the stop bit length. (Same specifications as P.E023)
Select the stop bit length and data bit length. (Same specifications
Select the parity check specifications.
(Same specifications as Pr.120)
Set the permissible number of retries for unsuccessful data
(Same specifications as Pr.121)
RS-485 communication is available, but the inverter trips in the NET
Set the interval of the communication check (Signal loss detection)
(Same specifications as Pr.122)
No communication check (Signal loss detection)
Set the waiting time between data transmission to the inverter and
(Same specifications as Pr.123)
Select the presence/absence of CR/LF.
(Same specifications as Pr.124)