Mitsubishi Electric FR-E700 Instruction Manual page 374

Communication operation and setting
Communication procedure
Data communication between the computer and inverter is made in the following procedure:
Fig. 6-121: 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 ex-
ternal 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. 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
inverter (Data
for error)
Computer processing delay time
Answer from
computer in
response to
reply data
(Data
checked for
error)
Tab. 6-68: 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 6-239.)
The inverter response to the inverter reset request can be selected. (Refer to page 6-243,
Tab. 6-73.)
When any of "0.01 to 9998" is set in Pr. 37 and "01" in instruction code HFF sets data format
to "A2" or "E2". In addition, data format is always A2 and E2 for read or write of Pr. 37.
6 - 234
Computer
⇓ Data flow
Inverter
Inverter
⇓ Data flow
Computer
No error
(Request accepted)
) is checked
With error
(Request rejected)
No error
(No inverter
processing)
With error
) is
(Inverter
reoutputs )
When data is read
When data is written
Run Running Parameter
Command Frequency Write
A A
A1
A2 A2
Present Present Present
C C C
D D D
10ms or more
Absent Absent Absent
Absent Absent Absent
Parameter
I000030C
" to the computer
Inverter Parameter
Monitor
Reset Read
A B B
Absent Present Present
E
E
C E1
E2
E2
D D D
Absent Absent
Absent
(C) (C)
Absent F F