Anonymous
Mar 23, 2026
Rating: 5/5
Perfect for RPM projects
This module works flawlessly with my Arduino tachometer project. The signal is clean and the response time is very fast. Highly recommended for motor testing.
Description
Reviews
| Brand | - |
| Category | Robotics / STEM Teaching Tools / Sensors |
| Origin | - |
| Operating Voltage | 3.3V - 5V DC |
| Output Signal | Digital TTL Level |
| Sensor Type | Slot-Type Optocoupler |
| Slot Width | 5mm |
| Response Time | < 10 microseconds |
| Max Frequency | 20 kHz |
| LED Indicator | Yes (Power and Signal) |
| Mounting Hole Diameter | 3mm |
| PCB Dimensions | 32mm x 14mm |
| Interface Pins | VCC, GND, OUT |
Anonymous
Mar 23, 2026
Rating: 5/5
Perfect for RPM projects
This module works flawlessly with my Arduino tachometer project. The signal is clean and the response time is very fast. Highly recommended for motor testing.
Anonymous
Mar 17, 2026
Rating: 5/5
Exactly as described
Arrived quickly and worked immediately upon connection. The slot width is perfect for standard encoder disks. No noise issues observed.
Anonymous
Mar 07, 2026
Rating: 4/5
Great for learning
Used this for a university lab experiment on motor control. It provided consistent data. Would be nice if it came with a sample code sheet, but online resources are plentiful.
Anonymous
Mar 07, 2026
Rating: 4/5
Good value, easy to use
Very straightforward to wire up. The LEDs make debugging easy. I deducted one star because the mounting holes are a bit tight for standard screws, but overall a great sensor.
Anonymous
Mar 06, 2026
Rating: 5/5
Reliable speed counting
I used this to count rotations on a small DC motor. It handles high speeds without missing pulses. The build quality feels solid for the price.
Anonymous
Mar 02, 2026
Rating: 5/5
Bulk buy success
Purchased ten of these for our workshop. All units tested perfectly. The optocoupler isolation is a nice feature for protecting microcontrollers.
Q: What is the maximum width of the object that can pass through the slot?
A: The slot width is approximately 5mm. Any opaque object thinner than 5mm can interrupt the beam to trigger a signal.
Q: Can I use this to measure water flow if I attach a spinner?
A: Yes, as long as the spinner has vanes that fit within the 5mm slot and rotate at a frequency under 20kHz, it will work effectively for flow measurement.
Q: Does this output analog or digital signals?
A: This module outputs a digital TTL level signal. It switches between HIGH and LOW states when the slot is blocked or unblocked.
Q: Can this module work directly with a 3.3V microcontroller like ESP32?
A: Yes, the module supports an operating voltage range of 3.3V to 5V, making it fully compatible with 3.3V logic systems like the ESP32.
Q: Is there a pull-up resistor included on the board?
A: Yes, the PCB includes necessary circuitry including pull-up resistors, so you can connect the OUT pin directly to your microcontroller input.