Mitsubishi Electric MELSEC-Q Series Programming Manual page 149

No. Execution Type

Stand-by type program (wait)
 Fixed scan execution type program
(Fixed scan)
*1 The low-speed execution type program execution is not available for the Redundant CPU, Universal model QCPU, and LCPU.
*2 Only one program is allowed for the Universal model QCPU and LCPU.
*3 The Universal model QCPU and LCPU do not support SFC programs for program execution management.
• When the SFC program set as a stand-by type program is to be started, the SFC program in execution must
be switched to a stand-by type program before it is started. Refer to Page 148 Execution type designation
by instructions for the method of switching between the scan execution type program and stand-by type
program.
• Specify the execution type of each program file in "Program" of the PLC parameter dialog box.
• In the "Program" of the PLC parameter dialog box, set the normal SFC program to the number higher than
that of the SFC program for program execution management. If the normal SFC program is set to the
number lower than that of the SFC program for program execution management, an error may occur when
the SFC program set as a stand-by type program is started.
5.2 Whole Program Processing of High Performance Model QCPU, Process CPU, Redundant CPU, Universal Model QCPU, and
Description
• Programs such as a subroutine program and
interrupt program.
• Started by the program START instruction for
execution.
Program executed in a fixed cycle.
SFC Compatibility
Max. 124 programs (changes depending on the CPU
module type)
SFC program
• Normal SFC program: Multiple programs can be set
• SFC program for program execution management:
Cannot be set

5 SFC PROGRAM PROCESSING SEQUENCE
5
147