Cautions On Programming - Mitsubishi FX3U-USB-BD User Manual

FX Series PLC User's Manual - Data Communication Edition
Inverter Communication
9.3.4

Cautions on programming

1. Using inverter communication instruction together with another instruction
• Inverter communication instruction using ch1 cannot be used together with RS instruction.
• Inverter communication instruction cannot be used together with RS2 instruction if RS2 instruction uses
the same channel.
2. When programming inverter communication instruction in a state of STL instruction
Make sure to let the state relay remain ON until communication with an inverter is completed. If the state relay
is set to OFF during communication, inverter communication instruction is stopped in the middle of execution,
and another inverter communication instruction cannot be started. Program a sequence while observing the
following cautions
• Add M8029 (instruction execution complete flag) ON condition to the state relay transfer condition, and
provide such interlock that the state relay ON/OFF status does not change during communication with an
inverter.
If the state relay is set to OFF during communication, the remaining communication can be completed by
setting the state relay to ON again.
• When resetting many state relays all at once using the ZRST (FNC 40) instruction, etc., make sure that the
M8151 or M8156 (communication port busy) condition is OFF.
X000
Reset input
M0
3. Using inverter communication instruction in a program flow
Inverter communication instruction cannot be used in the following program flows
Program flow disabling inverter communication instruction
Between FOR and NEXT instructions
Between P and SRET instructions
Between I and IRET instructions
4. Caution on writing during RUN
1) Condition in which inverter communication instruction can be written:
While the PLC is in the STOP status, inverter communication instruction can be written during RUN.
2) Condition in which inverter communication instruction cannot be written:
Inverter communication instruction cannot be written during RUN by programming software in a personal
computer.
If an inverter communication instruction is written during RUN during communication or if an inverter
communication instruction is deleted while in RUN, communication may be disabled after that. (In such a
case, set the PLC to STOP, and then to RUN mode again to initialize the status.)
5. When using the E500 Series
Parameters Nos. 922 and 923 in the E500 Series cannot be used in inverter communication.
M8151
FNC 40
ZRST
Communication
port busy
Between CJ and P instructions
9 Creating Programs (for FX3G, FX3U and FX3UC PLCs)
9.3 Common Items in Inverter Communication Instructions
SET M0
State relays S0 to S999
S0 S999
are reset all at once.
RST M0
Remarks
Conditional jump
Repeat
Subroutine
Interrupt routine
A
B
C
D
E
F
G
H
I
Apx.
E-89