Counter - Mitsubishi Electric MELSEC iQ-R Series User Manual

Counter

This device counts the number of rising operation of the input condition in the program. The counter is an up-timing type
device and therefore when the count value matches a setting value, the count reaches its upper limit and the contact is turned
on.
Types of counters
There are two types of counters: counter (C) which retains the counter values in 16-bit units and long counter (LC) which
retains them in 32-bit units. The counter (C) and the long counter (LC) are different devices and the number of device points
can be set for each of them.
■Counter (C)
This device uses one word for each point. The measurable range is 0 to 65535.
■Long counter (LC)
This device uses two words for each point. The measurable range is 0 to 429467295.
The long counter (LC) can be used in interrupt programs. ( Page 115 Interrupt Program)
Counting process
When executing the counter coil (OUT Cinstruction / OUT LCinstruction), the counter coil is turned on/off, the current
value is updated (count value +1), and the contact is turned on/off. The current value is updated (count value +1), when the
counter coil input is rising (from off to on). The current value is not updated when the coil input is off, remains on, and is turned
off.
[Ladder example]
X0
[Update timing of the current value]
END
Program
ON
X0
OFF
Coil of C0
OFF
Update of the current value
K10
C0
OUT C0 END OUT C0
ON
END OUT C0
Update of the current value
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27 DEVICES
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27.3 User Device