Hall sensor connections

I have what I believe is a Hall sensor removed from a shower pump where it was used to sense rotation of the pump

Unfortunately the sensor is potted and has no identifying marks nor any indication of what its 3 wires do. The 3 wires are unhelpfully coloured red, orange and yellow so, assuming that red is positive it is a guess as to which of the others is GND and which is digital out

Is it possible by measurement of resistance, perhaps with and without a magnet close to the sensor, possible to determine which wire is which ?

I know how to read a Hall sensor so If I go with my inclination and just try both possible arrangements (if red is 5V) with a 10K resistor between 5V and a second wire am I likely to damage the sensor and try reading the output using digitalRead() ?

Sometimes maybe. Not knowing the part, your skill set and tools I could not predict what would happen. Hall Sensors are very cheap devices with shipping generally more than the part. I would suggest try it with the assumption you will fry it. If you don’t and it works it is your lucky day!

I think that I am going to dive in and experiment. I don’t actually have a need for the sensor but could find a use for it.

One thing that does attract me to it is that it is potted which could come in useful as a possible use would be to count wheel revolutions on a mobility scooter.

I understand your reticence not knowing my skill level, but I have the skill level and equipment to test it to the level that I described, so stand well back. I am going in !

The results are in

It is a Hall sensor and it works


Great Job and you proved your skill.

3 wires? if its an active hall switch, try connecting power through 1k resistor, then looking
at the supposed output as the motor turns. 1k will prevent damage should you have the
connections wrong - repeat for all 6 possible pinouts.

Thanks Mark, but I am all sorted

Taking a wild guess that the red wire was 5V I sussed out the other two by trial and error