Tach-Ammeter project

Hello all, new here and have a feasibility question. My planned project is to change my tachometer and use as an ammeter for my electric vehicle conversion. My rough basic plan is to use a closed loop hall effect current sensor and an Arduino to change the voltage to the corresponding frequency to drive the tach needle which would show the actual current being drawn from the batteries during operation. I am working at logging the frequencies which drive the tach now, but thought I would check with those who have a higher pay grade than this newb with concerns to the feasibility and practicality of using an Arduino in this manner. 8)

Thanks in advance for any thoughts on this!


Hi Jim,

Sounds like a fun and practical project. I'm wondering if using a shunt is a better idea than hall effect sensor, perhaps someone else can offer their experience.

Best of luck!


Thanks j514, a shunt would be great since they are IMHO much more accurate, but am limited on space (it is a Vespa scooter) not much space left after all components and batteries are in place so was trying to keep the unit as small and compact as I can and figured it would be easier, and a little space savings, to have the primary battery cable run through a project box with hall effect and the Arduino rather than a shunt with additional lugs and separate mounting areas for the components, plus I'd rather keep my primary battery cables in one piece! ;)