Mitsubishi Electric melsec q00ucpu, Руководство пользователя

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CHAPTER9 DEVICES
9
2
3
4
5
6
7
8
9.2 Int
ernal User Device
9.2.10
Timer (T
)
9 - 25
(8)
Precautions for using timers
(a) Use of the same timer
Do not use the OUT T instruction that describes the same timer more than once within one scan.
If this occurs, the current timer value will be updated by each OUT T instruction execution, resulting in
incorrect time measurement.
(b) When the timer is not executed in every scan
While a coil of a timer (for example. T1) is on, do not make the
OUT T1 instruction jumped to any other
part with another instruction such as CJ.
If jump of the OUT T instruction has occurred, the current timer value is not updated.
Also, if a timer exists in a
subroutine program, execute a subroutine call including the OUT T1
instruction once in each scan while the coil of the timer (for example, T1) is on.
Failure to do so will not update the current timer value.
(c) Programs that cannot use timers
Timers cannot be used in interrupt programs and fixed scan execution programs.
(d) When the set value is 0
The contact turns on when the
OUT T instruction is executed.
(e) When the set value is changed after time-out
Even if the set value is changed to a larger value after time-out of the timer, the timer remains timed-
out and does not start the operation.
Figure 9.27 When the same timer is used
END END
OUT
T OUT
T OUT
T OUT
T OUT
T
Current value is updated.
Sequence
program
1 scan