Mitsubishi Electric MELSEC-Q00U(J)CPU

120
(a) Condition
The constant scan time needs to satisfy the following relational expression.
If the sequence program scan time is longer than the constant scan setting time, the CPU module detects
"PRG. TIME OVER" (error code: 5010).
In this case, the constant scan setting will be ignored and the sequence program scan time will be applied.
If the sequence program scan time is longer than the WDT setting time, the CPU module detects "WDT
ERROR".
In this case, the program execution will be stopped.
(3) Waiting time from when END processing is executed until next scan starts
Sequence program processing is stopped during the waiting time from when END processing of a sequence
program is executed until next scan starts.
(a) When an interrupt factor occurs during waiting time
Either of the following programs is executed.
• Interrupt program
• Fixed scan execution type program
(b) When a service processing parameter is set
The communication service processing with peripherals (such as programming tools) and intelligent function
modules is enabled during the waiting time by setting a service processing parameter. ( Page 240,
Section 3.24.1)
(WDT setting time) > (Constant scan setting time) >
(Sequence program maximum scan time)
0
12
3
412
3
4
00
1
END 0END
2
3
412
3
4
0END 0END
3.5ms 0.5ms
4ms 4ms
3.5ms 3.4ms 0.6ms
4ms5.3ms
5
ms
0.5ms
Scan where the constant scan setting is not applied
Constant scan setting (4ms)
Constant
scan
Sequence
program