I was wondering if a 12v auto starter relay could be used for system testing. (50amps max) I was wanting to test the difference between 24v and 36v on my new bike. The first one runs on 24v, and I have an identical motor that I was considering overvolting to 36v.(controller choice) Contactors are made in different amps/voltages. I understand more amps means larger,thicker contacts. But on the voltage side, is it that they have different windings for each voltage to control it? So being, can I run 24v/36v through the main connecters, and use only 12v to turn it on and off?