HiLetgo 5pcs Hall Effect Magnetic Sensor Module 3144E A3144 Hall Effect Sensor DC 5V for Arduino PIC AVR Smart Cars

I used these for an Arduino based model trolley reverser, They work great and have enough range. The circuit allows for a pullup resistor if needed.

The sensor component was soldered on in the wrong direction for all 5 I received.

Funcionaron bien

When I received the sensors they were all mangled because it was badly packaged

I needed a simple RPM tester so I put together some simple Python code. Connected the Hall effect board to my PI. The board has '-' clearly marked for GND at the connector. I connected that to pin 6 on my PI. '+' is not marked on the board but is the middle pin, so I connected that to pin 2, 5V, on my PI. Then the status line, marked with an 'S' to GPIO18 which is physical pin 12 on the PI. Note the boards status line is open collector, meaning it is either open or GND. It does NOT swing up 5V. In the Python code I did set the GPIO18 pin to be pulled up by the PI, not sure if I needed that since that may be the default. I tested my simple code on all 5 of the boards I received and they all worked as expected. I could easily detect an RPM from 30 to 400 RPM. Sorry that is NOT the limit of the circuit, just my hand tool. This little board is very inexpensive and works perfectly.