Mitsubishi Electric FR-A700 Instruction Manual page 629

Parameter
Communication procedure
Data communication between the computer and inverter is made in the following procedure:
Fig. 6-221: Schematic diagram of data exchange
If a data error is detected and a retry must be made, execute retry operation with the user
program. The inverter comes to an alarm stop if the number of consecutive retries exceeds
the parameter setting.
On receipt of a data error occurrence, the inverter returns "reply data
again. The inverter comes to an alarm stop if the number of consecutive data errors reaches
or exceeds the parameter setting.
Communication operation presence/absence and data format types
Data communication between the computer and inverter is made in ASCII code (hexadecimal
code). Data is automatically converted to ASCII format when it is exchanged between an exter-
nal computer and the frequency inverter. In the following table the different data formats are
referred to with the letters A – F. The corresponding formats are explained in the next section.
No.
Tab. 6-134: Communication and data format
In the communication request data from the computer to the inverter, 10ms or more is also
required after "no data error (ACK)". (Refer to page 6-453.)
The inverter response to the inverter reset request can be selected. (Refer to page 6-459,
Tab. 6-139.)
FR-A700 EC
Computer
⇓ Data flow
Inverter
Inverter
⇓ Data flow
Computer
Operation
Communication request is sent to
the inverter in accordance with the
user program in the computer.
The inverter will not send data
unless requested.
Reply data from the
No error
inverter (Data ) is
(Request
checked for error)
accepted)
With error
(Request
rejected)
Computer processing delay time
Answer from
No error
computer in
(No inverter
response to reply
processing)
data (Data ) is
With error
checked for error)
(Inverter re-
outputs
Communication operation and setting
When data is read
When data is written
Run Running
Com- Fre-
mand quency
A
A
A'
Present Present
C C
D D
Absent Absent
Absent Absent
Absent Absent
)
" to the computer
Parame-
Inverter Moni-
ter
Reset tor
Write
A A B
Present Absent Present
E
C C
E'
D D D
Absent Absent Absent
Absent
Absent Absent
(C)
Absent Absent F
I000030C
Parame-
ter Read
B
Present
E
D
Absent
Absent
(C)
F
6 - 449