Mitsubishi Electric FX3U-232-BD User Manual page 419

FX Series PLC User's Manual - Data Communication Edition
Inverter Communication
- The PLC waits for 15 ms after acquiring the communication port, and then starts communication using
EXTR instructions. Even if the drive condition turns ON, the PLC does not start execution of the EXTR
instruction until the communication port busy flag M8155 turns OFF from ON if M8155 was set to ON by
another EXTR instruction.
The PLC frees the communication port, and then executes EXTR instructions driven in the next step and
so on.
M0
M1
M0
EXTR
instruction [1]
(Communicating)
M1
EXTR
instruction [2]
(Communicating)
M8155
*1. The PLC does not execute the instruction even if M8155 is turned OFF because the drive contact is
OFF.
*2. When two or more instructions are driven at the same time during communication, the next EXTR
instruction is executed after the current instruction is completed.
*3. M8155 remains OFF until the next EXTR instruction is driven after execution of the current EXTR
instruction is completed.
2) Cautions on programming
When the drive contact for another EXTR instruction is driven by a pulse signal during communication
with an inverter, the communication is not executed.
When communicating with inverters for two or more items, let the drive contact for the EXTR instruction
remain ON until sending is completed. After communication with all inverters is completed, set the drive
contact to OFF using the instruction execution complete flag M8029.
X001
M0
M8029
Instruction execution
complete
3. Communication complete flag (M8029)
When communication with an inverter is completed, the instruction execution complete flag M8029 turns ON,
and remains ON for 1 scan.
For details on using M8029 method, refer to program examples shown below.
FNC180
 
EXTR
FNC180
 
EXTR
*1
15ms
15ms
EXTR EXTR
instruction [1] instruction [2]
FNC180

EXTR
7.2 Common Items in Inverter Communication Instructions
......[1]
 
......[2]
 
15ms
EXTR
instruction [1]
SET M0
Command is latched
Communication is
  
executed
Command is reset
RST M0
7 Creating Programs (FX2N, FX2NC)
*2
15ms
*2
15ms
EXTR EXTR
instruction [2] instruction [1]
*3 *3
E-77
A
B
C
D
E
F
G
H
I
Apx.A