Mitsubishi Electric FR-A820-00046 (0.4K), Instruction Manual

Page: 838 / 1218

(N) Operation via communication and its settings Parameters
5 - 636
[Parameters related to communication with the RS-485 terminals]
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.
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 page 5-655.)
$
When the Modbus® RTU communication protocol is selected, the stop bit length without parity
check can be selected between 1 bit and 2 bits. (Refer to page 5-655.)
%
In the Modbus® RTU protocol, this is invalid.
Pr. Name
Initial
value
Setting
range
Description
331
N030
RS-485 communication
station number
0
0 to 31
(0 to 247)
Set the inverter station number.
(Same specifications as Pr. 117)
332
N031
RS-485 communication
speed
96
3, 6, 12, 24,
48, 96, 192,
384, 576,
768, 1152
Select the communication speed.
(Same specifications as Pr. 118)
N032
RS-485 communication
data length
0 0, 1
Select the data length.
(Same specifications as P.N022)
N033
RS-485 communication
stop bit length
1 0, 1
Select the stop bit length.
(Same specifications as P.N023)
333
RS-485 communication
stop bit length / data
length
1 0, 1, 10, 11
Select the stop bit length and data bit length.
(Same specifications as Pr. 119)
334
N034
RS-485 communication
parity check selection
2 0, 1, 2
Select the parity check specifications.
(Same specifications as Pr. 120)
$
335
N035
%
RS-485 communication
retry count
1
0 to 10,
9999
Set the permissible number of retries for unsuccessful
data reception. (Same specifications as Pr. 121)
336
N036
%
RS-485 communication
check time interval
0 s
0
RS-485 communication is available, but the inverter trips
in the NET operation mode.
0.1 to
999.8 s
Set the interval of the communication check (signal loss
detection) time. (Same specifications as Pr. 122)
9999 No communication check (signal loss detection)
337
N037
%
RS-485 communication
waiting time setting
9999
0 to 150
ms, 9999
Set the waiting time between data transmission to the
inverter and the response. (Same specifications as Pr. 123)
341
N038
%
RS-485 communication
CR/LF selection
1 0, 1, 2
Select the presence/absence of CR/LF.
(Same specifications as Pr. 124)
NOTES The monitored 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 page 5-645.)
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.
Upon delivery the FR-A800-E inverter models are not equipped with the RS-485 terminal block.