How to measure engine fan RPM?

Sensors Distance
1

I am interested in counting the RPMs of my truck’s engine fan. It has a fan clutch that normally moves the fan at less than the engine RPM. Upon higher air temps the fan clutch fully engages and the fan is then in sync with the engine. I’d like to measure my fan’s RPMs and compare this to engine RPM, ambient temp, coolant temp, etc. to see how it’s performing.

Is there an Arduino compatible sensor that would be suitable for such a task? I’m imagining putting something reflective or magnetic on one of the fan blades and then having the sensor count how many times it goes around per second.

Does something like this sound possible?

Thanks for any ideas,

-Matt

2

Hi, what you’re planning to do is possible. You can use a magnetic encoder or you can use a hall effect sensor. You can even you an IR sensor. Many options are available. Here are some materials that you may find helpful:

https://www.instructables.com/Reading-D … h-Arduino/

https://www.pcbway.com/project/question … rpm__.html

https://www.youtube.com/watch?v=E5A4xgvvL84

3

That is such a cool/practical application. In addition to the links provided by rpiloverbd you can also check these ones:

https://learn.adafruit.com/pro-trinket-tachometer

https://blog.adafruit.com/2017/06/22/fi … essed-air/

https://blog.adafruit.com/2017/08/14/sp … led-strip/