OMRON EE-SY310 photo reflective sensor
This sensor is also available on a breakout board with all necessary components to interface it directly to your microcontroller.
What it is:
- Dark ON model (EE-SY310)
- Digital output HIGH/LOW depending if it detects a dark/bright spot
- Meant to detect revolutions on spinning wheels/gears that are marked with a dark spot
- can also be used to detect a water meter dial or a conventional electric meter containing a spinning dial with a dark line
- wide supply voltage range: 4.5 to 16 VDC. Tested to work fine at 3.3V, otherwise can be hooked to the VIN pin on the Moteino to give it the same voltage as the Moteino power input. IOW it will work with anything above ~3V (not tested at more than 5V though).
- Can be tested simply by hovering it over a blank piece of paper with a dark spot (marker or anything else). As you transition from light to dark you should see the input transition between HIGH/LOW
- The distance to the target should be around 5-10mm for optimal detection
- you should avoid using it in sunlight, as it will stall to LOW, unless you can shade/cover it