For my Senior Physics project due June 7th, I am making a tachometer using Arduino, a 3144 Hall-effect switch, and a 16x02 i2C LCD. I have the wiring as, 5v ---> VCC GND ---> GND D2 ---> Vout a resister of 10K Ohms is placed on my breadboard between VCC and Vout. and for the LCD 5v ---> VCC …

spinnerrpm_v2_2_ino.ino (1.6 KB) File for the code

Assuming your code works, it's not really an Arduino question - just math. Try increasing your sample time.

Yes while I am aware of this, being so unfamilar makes looking at it quite daunting, so I seeked assistance from those who are familar. Thought I was supposed to be decreasing the sample time, I'll give this a try now.

changing my sample time only makes it more inaccurate. If I change sample time from 1000 to 2000, my RPM simply halves from 60 to 30. I need more frequent counts I think?

What is your hall sensor connected to? How many RPM are you expecting?

It's connected to my Arduino, that's it. I'm only experimenting with a toy car wheel, only getting intervals of 60, should definitely be less than 60RPM.

At sixty RPM or less, with your sample time of one second, you're going to get at most one tick from the Hall. The only way to get better accuracy is to increase the time substantially.

What time must be increased substantially? The time it is measuring for or the sample time? I am not seeing how increasing the sample time does not just make it innacurate. If i double it, my RPM halves, like you said it's just math.

The problem is the sample time. You're spinning the wheel so slowly that the Hall provides one or no pulses in a second. It sounds like even two seconds isn't enough. Try ten.

3144 Hall Switch Tachometer Code: Getting RPM in smaller intervals than 60?

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Ballscrewbob May 27, 2021, 12:16pm 3

Edited your first post for you to include CODE TAGS ( </> )

Hall Sensor Tachometer Code printing strangely small values

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3144 Hall Switch Tachometer Code: Getting RPM in smaller intervals than 60?

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