Mitsubishi Electric FR-A700 EC, Инструкция по эксплуатации

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Parameter Communication operation and setting
FR-A700 EC 6 - 467
6.23.6 Modbus-RTU communication (Pr. 331, Pr. 332, Pr. 334, Pr. 343, Pr. 539,
Pr. 549)
Using the Modbus-RTU communication protocol, communication operation or parameter set-
ting can be performed from the RS-485 terminals of the inverter.
Pr. No. Name
Initial
Value
Setting
Range
Description Parameters referred to
Refer to
Section
331
RS-485 communication
station number
0
0 Broadcast communication is selected —
1–247
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 va-
lue 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 communica-
tion errors during Modbus-RTU com-
munication. Reading only
539
Modbus-RTU communica-
tion 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.
0.1–999.8 s
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
NOTES When Modbus RTU communication is performed with "0" (initial value) set in Pr. 331 "RS-
485 communication station number",broadcast communication is selected and the inverter
does not send a response message to the master. When response from the inverter is nec-
essary, set a value other than "0" in Pr. 331. Some functions are invalid for broadcast com-
munication. (Refer to page 6-470.)
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 section 6.22.3.)