Re: Custom Tachometer - Electronics related queries Quote:
Originally Posted by Rehaan I'm not agreeing or disagreeing with you here - but i want to know your reason for saying so. |
Hey Rehaan, the main reason we require a tachometer is to tune the CVT, for which we need to compare the RPM of the engine with that of the driven pulley.
Since the driving and driven pulley are in the same enclosure, it's easier to set up the system that way.
If I'm going to measure pulses from the spark plug, I'll have to ensure the signal is conditioned properly for the arduino, using a 7805 will introduce a slight lag which may or may not matter,
I'll need to use a 555 which requires very precise values of components to produce a +- 15 RPM accuracy, transistors, and of course it's own power supply. The car doesn't have an alternator and we need to preserve whatever battery power we can, every little bit helps.
I'll also have to estimate the number of turns to make around the plug depending on the gauge of the wire, etc.
Using a voltage divider will complicate the circuit(not that it's complex, but more so than the hall circuit).
Overall, it's only the practical aspect of using a spark plug coil vs hall sensor that favors the hall sensor more for our requirement, hope I've been of help! :P |