Timer Processing Method And Accuracy - Mitsubishi Electric 700 Series Programming Manual

(2) 100ms retentive timers
1) A 100ms retentive timer is designed to time the ON period of the timer coil.
When its coil turns on, the timer starts timing the present value and maintains
the present value and contact ON/OFF state if the coil turns off.
When the coil turns on again, the timer resumes timing from the maintained
present value.
2) Use the RST T
Ladder example
Timing chart
X5
OFF
T5 coil
OFF
Timer present
value
T5 contact
OFF
3.9.6

Timer processing method and accuracy

(1) Timer processing method
The coil of the timer is turned on/off at execution of the OUT T
the timer's present value is updated and its contact turned on/off at execution of
the END instruction.
1) When the coil of the timer turns on, the present value of that timer is updated
after execution of the END instruction, and when the timer times out, its contact
turns on.
(a) When the coil of the 10ms or 100ms timer turns off, the present value of
that timer is reset to 0 and the contact is also turned off after execution of
the END instruction.
(b) If its coil turns off, the 100ms retentive timer maintains the prevent value
and contact ON/OFF state.
2) When the timer is reset by the RST instruction, the present value of the timer is
reset to 0 and the contact turns off too at execution of the RST T
POINT
If the timer setting is "0", the setting becomes infinite and the timer does not time out.
instruction to clear the present value and turn off the contact.
ON
OFF
ON
OFF
15s
Fig 3.16 Timing Chart
Description of devices
Times ON of X5 for 20s.
Resets T5 contact and clears
present value when X6 turns on.
ON
ON
5s
ON
OFF
OFF
Setting
OFF
instruction, and
3
instruction.
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