yes on 120v electric, the white is neutral(neg) and black is hot(pos). white is always neutral when running 120v and your colored wires are hot. black, blue, red, etc. yes the ground(green) can just be cut off and taped. if your using a 3 prong cord to feed your express, you should just break off the ground prong on the cord cap itself so that the wire inside the express never becomes an issue.