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

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.

This worked well for me. Note however that the sensor is sensitive to the polarity of the magnet. Make sure to test it and orient the magnet and which side of the sensor works with it.

Wired this circuit board with a built in LED, to a 3 to 5 Volt power supply and monitored the output signal with both a digital multimeter and Oscilloscope. Moving a magnet at different speeds across the Hall Effect Transistor, enables me to view a varying square wave shaped pulse width modulated signal. My main focus was to use this as a learning tool, and I was not disappointed. The price is right as well.

Functions as advertised.

good

Works like a charm.

I love these little guys. They work perfectly with the little mini magnets I purchased.

Tested each Hall Effect Sensor that was received and none of them ended up testing any good on my workbench - a shame really. So then I decided to test each sensor by removing them from the PCB, because why not?... Well, as it turns out, all the sensors are good, it's just that there's something going on with the PCB, it just isn't engineered the way you'd expect it, the PCB traces are not one for one... So my recommendation is, steer clear of this brand, at least until they sort out their PCB issues because without the proper documentation, this won't be a straight forward use product.