Counters C - Mitsubishi Electric 700 Series Programming Manual

3.10 Counters C

The counters of the built-in PLC function are up counters.
An up counter stops counting and its contact turns on when the count value reaches
the setting.
(1) Count processing
1) The coil of the counter is turned on/off at execution of the OUT C
and its present value is updated and its contact turns on after execution of the
END instruction.
2) The counter counts on detection of the leading edge (OFF to ON) of the coil. It
does not count if the coil remains on.
(2) Counter resetting
1) The count value is not cleared even if the coil turns off. Use the RST C
instruction to clear the count value and turn off the contact.
2) When the counter is reset by the RST instruction, the present value and
contact of the counter are cleared at execution of the RST instruction.
Ladder example
Input condition
Fig 3.18 Count Ladder
C0 counts on leading edge (OFF to ON)
of input X5.
Resets C0 when input X6 turns on.
Counters C
instruction,
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