Inductive speed pickup into Electron

Hi all,

Has anyone had any experience using an inductive speed pickup (2 wire) as an input to a Particle Electron? Is the signal strong enough to go straight into an interrupt pin, or is some type of amplificaiton required?


Hi Stoo,
Not 100% what kind of sensor you’re referring to, do you have a link?

Hi Sam,
not sure exactly what the sensors are yet, but something like this

One of them is counting teeth in a gear box (I think it is 50 teeth/revolution @ up to 750 rpm), with only two wires on the sensor, and the other is also just a two wire sensor on a fan, which I think is one pulse/rev @ up to 1400 rpm.

Thanks Stoo. Looks like that sensor outputs up to 10V peak to peak. If indeed 10V pk-pk then it will certainly damage your Particle Electron without a voltage step down in place (basic resistor voltage divider would suffice) along with something to protect from negative voltages (the -10V could be isolated with a fly back diode).

Perhaps in the code include a small delay after a rising / falling edges are detected, to avoid false hits triggered by noise / etc. Would be easiest to checkout the signal on a scope - that way you could make an educated guess with what delay would suit.

If the Vnoise is < 200mV then no need as Particle Electron I/O pins have schmitt triggers which should keep clean reads.