finitetime
Full Access Member
I'm not sure how a tach is built so this idea might be dumb. I use to have cheapo air compressor that had pressure gauge with two needles in it. One indicated the pressure the other one you turned up to the max pressure you wanted and shut the compressor off when the two needles touched. Could I do something like that in reverse or would it tear one one of the after tachs up. I could just set a point where needle touched something metal and grounded a relay.