132
PARAMETERS
<Computer programming>
(1) Communication protocol
Data communication between the computer and inverter is performed using the following procedure:
*1. If a data error is detected and a retry must be made, execute retry operation from the user program.
The inverter comes to an alarm stop if the number of consecutive retries exceeds the parameter setting.
*2. On receipt of a data error occurrence, the inverter returns "reply data 3)" to the computer again. The
inverter comes to an alarm stop if the number of consecutive data errors reaches or exceeds the
parameter setting.
(2) Communication operation presence/absence and data format types
Communication operation presence/absence and data format types are as follows:
* In the communication request data given from the computer to the inverter, 10ms or more is also required
after "no data error (ACK)". (Refer to page 134.)
(3) Data format
Hexadecimal data is used. Data is automatically transferred in ASCII between the computer and inverter.
(1) Data format types
1) Communication request data from computer to inverter
No. Operation
Run
Command
Running
Frequency
Parameter
Write
Inverter
Reset
Monitoring
Parameter
Read
1)
Communication request is sent to the inverter
in accordance with the user program.
A’ AAABB
2) Inverter data processing time Present Present Present Absent Present Present
3)
Reply data from
the inverter(Data 1)
is checked for
error)
No error* (Request
accepted)
C C C Absent
E
E’
E
With error (request
rejected)
D D D Absent F F
4) Computer processing delay time Absent Absent Absent Absent Absent Absent
5)
Answer from
computer in
response to reply
data 3)(Data 3) is
checked for error)
No error*
(No inverter
processing)
Absent Absent Absent Absent G G
With error.
Inverter outputs
3) again.
Absent Absent Absent Absent H H
*
1
*2
Computer
Inverter
↓
(Data flow)
Computer
↓
(Data flow)
Inverter
Data read
Data write
Time
1)
2) 3)
4)
5)
*1
ENQ
*4
123456789101112
13
*1
ENQ
*4
1234567891011
*1
ENQ
*4
123456789
[Data format]
Format A
[Data read]
Format A'
Format B
*2 Inverter
station
number
Instruction
code
*3
Waiting
time
Data
Sum
check
Instruction
code
Instruction
code
*3
Waiting
time
*3
Waiting
time
Data
Sum
check
Sum
check
←
Number of characters
←Number of characters
←
Number of characters
*2 Inverter
station
number
*2 Inverter
station
number
