Mitsubishi Electric 800 Series Instruction Manual page 132

Item
Character system
Start bit
Stop bit length
Communication
specifications
Parity check
Error check
Terminator
Time delay setting
 Communication procedure
• Data communication between the computer and inverter is made in the following procedure.
(a) Request data is sent from the computer to the inverter. (The inverter will not send data unless requested.)
(b) Communication waiting time
(c) The inverter sends reply data to the computer in response to the computer request.
(d) Inverter data processing time
(e) An answer from the computer in response to reply data (c) of the inverter is transmitted. (Even if (e) is not sent, subsequent
communication is made properly.)
Computer
↓ (Data flow)
Inverter a
Inverter
∗1
↓ (Data flow)
Computer
*1 If a data error is detected and a retry must be made, perform retry operation with the user program. The inverter output is shut off if the number
of consecutive retries exceeds the parameter setting.
*2 On receipt of a data error occurrence, the inverter returns reply data (c) to the computer again. The inverter output is shut off 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).
• Communication operation presence/absence and data format types are as follows.
Symbol Operation
Communication request is sent to the
a inverter in accordance with the user
program in the computer.
b Inverter data processing time
Reply data from the inverter
c (Data (a) is checked for an
error.)
d Computer processing delay time
Reply from computer in
e response to reply data c
(Data c is checked for error.)
*1 When Pr.53 = "4" and the data code HFF = 1, the data format is A2 or E2. (Refer to
*2 The data writing format is A2 and the data reading format is E2 for Pr.37. (Refer to
*3 In the communication request data from the computer to the inverter, the time of 10 ms or more is also required after an acknowledgment (ACK)
signal showing "No data error detected" is sent. (Refer to
*4 Reply from the inverter to the inverter reset request can be selected. (Refer to
*5 At mode error, and data range error, C1 data contains an error code. (Refer to
format D.
ASCII (7 bits or 8 bits can be selected.)
1 bit
1 bit or 2 bits can be selected.
Check (at even or odd numbers) or no check can be selected.
Sum code check
CR/LF (whether or not to use it can be selected)
Availability of the setting is selectable.
When data is read
∗2
d e
b c
When data is written
Operation
command
A, A1
With
*3
No error
C
(Request
accepted)
With error
(Request D
rejected)
10 ms or more
*3
No error
Without
(No inverter
processing)
With error
(Inverter
Without
outputs c
again.)
Description
Time
Running Multi Parameter
frequency command
*1
A2
A (A2) A (A2)
With With With
*5
C C
C1
D D D
Without Without Without
Without Without Without
page 137.)
page 137.)
page 135.)
page 137.)
page 141.) Except for those errors, the error is returned with data
3.4 Mitsubishi inverter protocol (computer link communication)
Related parameter
Pr.119
—
Pr.119
Pr.120
—
Pr.124
Pr.123
Inverter Parameter
Monitor
write reset
*2
A B B
Without With With
E, E1,
*4
C E (E2)
*1
E2, E3
*4
D D
D
Without Without
Without
(C) (C)
Without F F
3. RS-485 Communication
1
2
3
4
5
6
7
8
9
10
read
*2
131