Mitsubishi Electric FR-A700 Series, Technical Manual

Page: 409 / 550

443
PARAMETER
2
P
ARAM
ETE
R
2.21.4 Communication EEPROM write selection [Pr. 342]
(common
)
When parameter write is performed from the inverter PU
connector, RS-485 terminals, USB communication and
communication option, parameters can be written to the
RAM.
When changing the parameter values frequently, set [
Pr.
342 = 1 ] to write them to the RAM.
The life of the EEPROM will be shorter if parameter write is
performed frequently with [
Pr. 342 = 0 ] (initial value)
(EEPROM, RAM write).
When [
Pr. 342 = 1 ] (write to RAM only), powering OFF the
inverter will erase the changed parameter values.
Therefore, the parameter values available when power is
switched ON again are the values stored in EEPROM
previously.
[RS-485 terminal communication related parameter]
[Pr.] Name Initial Value Setting Range Description
331
RS-485 communication station
number
0
0 to 31 (0 to 247) *1
Set the inverter station number.
(same specifications as [
Pr. 117
] )
332 RS-485 communication speed 96
3, 6, 12, 24,
48, 96, 192, 384
select the communication speed.
(same specifications as [
Pr. 118
] )
333 *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
RS-485 communication parity
check selection
2 0, 1, 2
Select the parity check specifications.
(same specifications as [
Pr. 120
] )
335 *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
0
RS-485 communication is enabled. However, the
inverter will come to trip if operation is changed to
NET operation mode.
*5
0.1 to 999.8s
Set the interval of communication check time.
(same specifications as [
Pr. 122 ] )
9999 No communication check
337
*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
*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 0
0 Mitsubishi inverter (computer link operation) protocol
1 Modbus-RTU protocol
*4
*1 When [ Pr. 549 = 1 ] (Modbus-RTU protocol) is set, the setting range within parenthesis is applied.
*2 For the Modbus-RTU protocol, the data length is fixed to 8 bits and the stop bit depends on the [
Pr. 334
] setting. (Refer to
page 459)
*3 The Modbus-RTU protocol becomes invalid.
*4 The Modbus-RTU protocol of is only valid for the communication from the RS-485 terminals.
*5 If communication is made with [ Pr. 336 RS-485 communication check time interval = 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 alarm (E.SER) occurs after first
communication.
When performing operation or parameter write through communication, set [
Pr. 336 = 9999 ] or larger value. (The setting
depends on the computer side program.)
( Refer to page 449)
A700 F700
A700 F700
common
[Pr.] Name Initial Value Setting Range Description
342 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.
The above parameters can be set whenever the communication option is connected.