215
Communication operation and setting
4
PARAMETERS
[RS-485 terminal communication related parameter]
Parameter
Number
Name Initial
Value Setting Range Description
331 RS-485 communication
station number 0
Pr. 549
0 to 31 *6 Set the inverter station number. (same
specifications as Pr. 117 )
0
(Mitsubishi
protocol)
1
(Modbus-RTU) 0 to 247
2
(BACnet) 0 to 127 *6
332 RS-485 communication
speed 96
Pr. 549
3, 6, 12, 24,
48, 96, 192,
384 *6
Used to select the communication speed.
(same specifications as Pr. 118 )
0
(Mitsubishi
protocol)
1
(Modbus-RTU)
2
(BACnet)
96, 192,
384, 768 *6
333 *1*2 RS-485 communication
stop bit length 1 0, 1, 10, 11 Select stop bit length and data length.
(same specifications as Pr. 119)
334 *1 RS-485 communication
parity check selection 2 0, 1, 2
Select the parity check specifications.
(same specifications as Pr. 120)
335 *1*3 RS-485 communication
retry count 1 0 to 10, 9999
Set the permissible number of retries at
occurrence of a data receive error.
(same specifications as Pr. 121)
336 *3 RS-485 communication
check time interval 0s
0RS-485 communication is available, but the
inverter trips 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
337 *1*3 RS-485 communication
waiting time setting 9999 0 to 150ms, 9999
Set the waiting time between data
transmission to the inverter and response.
(same specifications as Pr. 123)
341 *1*3 RS-485 communication
CR/LF selection 1 0, 1, 2
Select presence/absence of CR/LF.
(same specifications as Pr. 124)
549 Protocol selection 1
0 Mitsubishi in verter (computer link) protocol
1 Modbus-RTU protocol *4
2 BACnet MS/ TP protocol *4
*1 Invalid during the BACnet MS/TP protocol.
*2 For the Modbus-RTU protocol, the data length is always 8 bits and the stop bit depends on the Pr. 334 setting. (Refer to page 232)
For the BACnet MS/TP protocol, the data length is always 8 bits and the stop bit is always 8 bit.
*3 Invalid during the Modbus-RTU protocol.
*4 The Modbus-RTU protocol and BACnet MS/TP protocol are valid for only communication from the RS-485 terminals.
*5 The above parameters can be set when Pr. 160 User group read selection = "0". (Refer to page 190)
*6 The inverter works with the initial parameter setting if a value other than the setting range is set.
......The specification di ffers according to the manufacture date. Re fer to page 400 and check the SERIAL.
CAUTION
⋅If communication is made without Pr. 336 RS-485 communication check time interval being changed from "0" (initial value), monitor,
parameter read, etc. can be performed, but the inverter results in an alarm as soon as it is switched to the NET operation mode.
If the operation mode at power ON is the Network operation mode, a communication fault (E.SER) occurs after first
communication.
When performing operation or parameter write through communication, set "9999" or m ore to Pr. 336. (The setting depends on
the computer side program.) (Refer to page 224)
⋅Always reset the inverter after making the initial settings of the parameters. After you have changed the communication -related
parameters, communication cannot be made until the inverter is reset.