Cautions On Programming - Mitsubishi Electric FX3U-232-BD User Manual

FX Series PLC User's Manual - Data Communication Edition
Inverter Communication
7.2.4

Cautions on programming

1. Using the EXTR instruction together with another instruction
• The EXTR instruction cannot be used together with the RS instruction.
• The EXTR instruction cannot be used together with a EXTR K0 instruction.
2. When programming the EXTR instruction in a state of a 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, the EXTR instruction is stopped in the middle of execution, and another
EXTR 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 an interlock that the state relay ON/OFF status does not change during communication with
an inverter.
If the state changes during communication, communication may not be performed normally.
• When resetting many state relays all at once using ZRST (FNC 40) instruction, etc., make sure that the
M8155 (communication port busy) OFF condition is established.
X000
Reset input
M0
3. Using the EXTR instruction in a program flow
The EXTR instruction cannot be used in the following program flows
Program flow disabling the EXTR instruction
Between CJ and P instructions
Between FOR and NEXT instructions
Between P and SRET instructions
Between I and IRET instructions
4. Caution on write during RUN
1) Condition in which the EXTR instruction can be written
While the PLC is in the STOP status, the EXTR instruction can be written during RUN.
2) Condition in which the EXTR instruction cannot be written
The EXTR instruction cannot be written during RUN.
If the EXTR instruction is written during RUN while communication or if the EXTR instruction is deleted in
RUN mode, 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.
E-80
M8155
FNC 40
ZRST
Communication
port busy
7.2 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
7 Creating Programs (FX2N, FX2NC)