Mitsubishi 00JCPU User Manual page 412

(d) Maximum counting speed
The counter can count only when the on/off time of the input condition is longer than the execution interval of
the corresponding OUT C instruction.
The maximum counting speed is calculated by the following expression:
When T1
When T1 < T2, n =
Count input signal
The maximum counting speed can be increased by placing multiple counters within one scan.
At this time, use the direct access input (DX
Sequence
program
9 - 37
Maximum counting n
=
speed (Cmax)
100
*1: Duty (n) is the ON-OFF time ratio of count input signal, and is expressed as a
percentage value.
T2
T2, n = 100%
T1+T2
T1
100%
T1+T2
ON
OFF
Figure 9.38 Duty ratio
)(
OUT OUT
END
C C
Figure 9.39 Ladder example for increasing the maximum counting speed
n: Duty (%)
1
[times/s]
T:
T
Execution interval of the OUT C
T1 T2
Section 3.8.2) for the counter input signal.
OUT OUT
END
C C
*1
instruction (sec)
OUT
C
Execution interval of the
OUT C instruction