20Pcs 49E OH49E SS49E S49E TO-92S Hall Effect Sensor 3Pins Magnetic Detector for Arduino

They all worked. It was convenient to purchase.

Perfect hall sensor for my bike twist throttle

muy bien

The one I tried worked. I had to look up the pin-out -- with leads down and the angled sides facing you (the flat side facing away from you), the left is +5VDC, middle is GND and the right is the output. Nominal output is 2.5VDC with no magnetic field. The direction of the output changed when the magnet was reversed. With just one 1/4" diameter disk magnet, the voltage range was 4.24V and the low was 0.80V with the magnet at the sensor; with two magnets the low went to 0.75V, the high was the same. With the two magnets, the output changed by 0.001V about 6 inches but remained that way until about 1/2 inch where the voltage was about 2.63 volts -- 0.13V change. A 3-inch stack of magnets was 2.68V. A 1 inch disk magnet gave 3.25V at 1/2 inch and 2.75V at 1 inch distance. At 2 inches the 1-inch magnet gave a change of 0.04V from the 2.5V nominal.

Many were mangled and show signs of use. I can’t trust a product that has been used and returned. Don’t waste your money.