Re: RPM tachometer, cadence meter
they are primarily designed for test rigs , hence both the 9999 rpm and 8-24 volt ( 12v-16v nominal ) a 3s lipo would provide a suitable source of power (11.8v) and depending on the resolution I would think it would / should be ok - would need to check the spec to see how accurate it is at such a low speed and if it suppresses the leading zeros .
But the warning is that usually the resolution at 100 rpm might be pretty poor .
Running a 10x pickup rotor would increase the speed to 0 -1000 but you would need to ignore the first zero ( / 10 ) or mask the digit .
These were just the easy ways , the spec sheet might be able to reconfigure the unit to a lower spec .
just a few ideas
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