# Initial Settings And Specifications Of Rs-485 Communication; (pr. 117 To Pr. 124, Pr. 331 To Pr. 337, Pr. 341, Pr. 549); Initial Settings And Specifications Of Rs-485 Communication (pr. 117 To Pr. 124, Pr. 331 To Pr. 337, Pr. 341, Pr. 549) - Mitsubishi Electric FR-A720-0.4K Instruction Manual

Fr-a700 series.

## 4.24.3 Initial settings and specifications of RS-485 communication

### (Pr. 117 to Pr. 124, Pr. 331 to Pr. 337, Pr. 341, Pr. 549)

Used to perform required settings for communication between the inverter and personal computer.
There are two different communications: communication using the PU connector of the inverter and
communication using the RS-485 terminals.
You can perform parameter setting, monitor, etc. from the PU connector or RS-485 terminals of the inverter
using the Mitsubishi inverter protocol (computer link communication).
To make communication between the personal computer and inverter, initialization of the communication
specifications must be made to the inverter.
Data communication cannot be made if the initial settings are not made or there is any setting error.
[PU connector communication related parameter]
Parameter
Name
Number
PU communication station
117
number
118
PU communication speed
PU communication stop bit
119
length
PU communication parity
120
check
Number of PU
121
communication retries
PU communication check
122
time interval
PU communication waiting
123
time setting
PU communication CR/LF
124
selection
Communication operation and setting
Initial Value
Setting Range
0
0 to 31
192
48, 96, 192, 384
0
1
1
10
11
0
2
1
2
0 to 10
1
9999
0
0.1 to 999.8s
9999
9999
0 to 150ms
9999
9999
0
1
1
2
Description
Specify the inverter station number.
Set the inverter station numbers when two or
more inverters are connected to one
personal computer.
Set the communication speed.
The setting value × 100 equals the
communication speed.
For example, the communication speed is
19200bps when the setting value is "192".
Stop bit length
Data length
1bit
8bit
2bit
1bit
7bit
2bit
Without parity check
With odd parity check
With even parity check
Set the permissible number of retries at
occurrence of a data receive error. If the
number of consecutive errors exceeds the
permissible value, the inverter will come to
an alarm stop.
If a communication error occurs, the inverter
will not come to an alarm stop.
No PU connector communication
Set the interval of communication check
(signal loss detection) time.
If a no-communication state persists for
longer than the permissible time, the inverter
will come to an alarm stop.
No
communication
check
detection)
Set
the
waiting
time
between
transmission to the inverter and response.
Set with communication data.
Without CR/LF
With CR
With CR/LF
4
(signal
loss
data
317