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3.4.23 Mitsubishi inverter protocol (computer link communication)
(1) Communication
The communication specifications are given below.
(2) Communication procedure
If a data error is detected and a retry must be made, perform retry operation with the user program. The converter stops retrying and outputs the LF signal
when the number of consecutive retries exceeds the parameter setting.
On receipt of a data error occurrence, the converter returns reply data 3) to the computer again. The converter stops retrying and outputs the LF signal when
the number of consecutive data errors exceeds the number set in the parameter.
You can perform parameter setting, monitoring, etc. from the PU connector of the converter using the Mitsubishi inverter
protocol (computer link communication).
Item
Description
Related
Parameters
Communication protocol
Mitsubishi protocol (computer link)
Conforming standard
EIA-485(RS-485)
Number of connectable devices
1:N (maximum 32 units), setting is 0 to 31 stations
Pr. 117
Communication speed
PU connector
Selected among 4800/9600/19200/38400bps
Pr. 118
Control procedure
Asynchronous
Communication method
Half-duplex
Communication
Character system
ASCII (7 bits or 8 bits can be selected.)
Pr. 119
Start bit
1bit
Stop bit length
1 bit or 2 bits can be selected.
Pr. 119
Parity check
Check (with even or odd parity) or no check can be selected.
Pr. 120
Error check
Sum code check
Terminator
CR/LF (presence/absence selectable)
Pr. 124
Waiting time setting
Selectable between presence and absence
Pr. 123
Data communication between the computer and
converter is made in the following procedure.
1) Request data is sent from the computer to the
converter. (The converter will not send data
unless requested.)
2) After waiting for the waiting time,
3) The converter sends reply data to the computer
in response to the computer request.
4) After waiting for the converter data processing
time,
5) An answer from the computer in response to
reply data 3) of the converter is transmitted.
(Even if 5) is not sent, subsequent
communication is made properly.)
When data is read
When data is written
1)
5)
4)
3)
2)
∗1
∗2
Computer
(Data flow)
Converter
Computer
(Data flow)
Converter
Time
HC2.book 98 ページ ２０１２年１１月１９日 月曜日 午前１０時５２分
