3. Setup
CNT24-2(USB)GY
25
Single-phase input with gate control
The counter can be started/stopped according to the gate control signal that is input
together with a string of single-phase pulses. The clear signal zero-clears the counter
value.
Because the pulses from an external signal can be measured in a segment of time,
measuring the rotational velocity is practicable.
For example, in following condition, the number of rotational velocity can be figured
out according to the measured number of pulses.
Measure time (the time that the gate is effective): 0.3 sec
The number of the encoder’s pulses per round: 200 pulses
Measured pulses: 1800 pulses
Rotational velocity = 1800
÷
(0.3 / 60)
÷
200 = 1800 rpm
If the measure time can be set by the resolution of the encoder in advance, the input
data will be the rotational Expansion velocity data.
Figure 3.10.
Single-phase Input with Gate Control
Count data
6
6
6
7
8
9
A
B
C
C
6
6
7
8
9
2 multiplier
1 multiplier
Phase-A
Phase-B
(Phase-A/UP)
(Phase-B/DOWN)
