In the process of building my ebike I came across problems of measuring current without putting a sense resistor in the power circuit. For that we build a USB based non invasive current sensor which measures current from -100A to +100A. We also did a kickstarter although It looks like not many people need such a thing. I am not tryying to promote it here but trying to get ideas on adding a non contact voltage sensor < Moderator Note -- kickstarter link deleted > In addition to sensing the current thru the loop I would like to sense the voltage of the wire. I am stymied any ideas on non contact voltage sensing similar to those ac power sensors sold by home depot but for DC and with 3 digit accuracy..