Introduction of Digital Counter
A Digital counter is an LED control instrument, which can be used for distance measurement, packaging counting and position control. The input signal can be various waveform pulse signals and sensor signals. The input signal can be various waveform pulses and sensor signals, such as grating, proximity sensor, photoelectric sensor, contact switch, encoder, etc. (NPN, PNP). The digital counter can be directly connected to the computer and PLC. It is widely used in food, machinery, packaging and other industries.
How it works
After setting the number, trigger the sensor. Each time it is triggered, the data increases by 1. When the set value is reached, OUT1 has an output.
PLC counter
The functions of PLC counters are basically similar to those of digital counters, but they are mostly used in automated logic control, which also requires the cooperation of input signals from various sensors.
Wiring explanation
At this time we can observe that the indicators of 0.03, 101.02 and relay KA are not on. When the light from the photoelectric sensor is blocked. The indicator lights of 0.03, 101.02 and relay KA are all on.
Omron PLC counter programing
- Establish an external trigger contact 10.00.
- Establish a counter CNT 000 and set the number of triggers to 8 (after accumulating 8 triggers, CNTOOO will act).
- Establish reset trigger point 10.01.
- Establish CNT trigger point (C00O), external output 100.00.
- Every time 10.00 is triggered, the counter is decremented by 1.
- When it is reduced to 0, C0O0 is triggered and 100.00 is output.
- When 10.01 is triggered, the digital counter is reset.
Simulation run
- Set 10.00 to 1, you can find that the counter setting value is reduced by 1.
- When the value is 0, C000 is triggered, and the PLC's 100.00 contacts are triggered.
- Turn 10.01 ON, and the counter CNTOOO will be reset.
If you want to see more details, please check the video:
