Mitsubishi MELSEC QS Series, User Manual

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9
DEVICE EXPLANATION
9.2 Internal User Devices
9.2.8 Timer (T)
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(8) Precautions for using timers
The following are a few precautions regarding timer use:
(a) Use of the same timer
A given timer cannot be designated (by OUT T ) more than once in a single
scan.
This designation results in measurement, since the timer current value is updated
at execution of each OUT T instruction.
(b) When set value is 0
If the timer set value is "0", the contact turnes ON when the OUT T instruction is
executed.
(c) When set value is changed after time-out
If the set value changes to a value which is higher than the current value following
a timer "time-out", the "time-out" status will remain in effect, and timer operation
will not be performed.
Diagram 9.23 When the same timer is used
END END
OUT
T
OUT OUT OUT OUT
Current value
is updated.
Sequence
program
1 scan
T T T T