Checking

• Floating Propulsion System Ground—No part of the propulsion system (batteries, controller, etc.) should be connected to any part of the vehicle frame.

This minimizes the possibility of being shocked when you touch a battery terminal and the body or frame, and of a short circuit occurring if any part of the wiring becomes frayed and touches the frame or body. • Accessory 12-Volt System Grounded to Frame—The 12-volt accessory system in most EV conversions is grounded to the frame, just like the electrical system of the internal combustion vehicle chassis it utilizes. The body and frame is not connected to the propulsion system, but it can and should be used as the ground point for the 12-volt accessory system, just as the original vehicle chassis manufacturer did. • Frame Grounded to AC Neutral When Charging—The body and frame should be grounded to the AC neutral line (the green wire) when an on-board or offboard AC charger is attached to the vehicle. This prevents electrical shock when the batteries are being charged. To guarantee shock-free performance, transformerless chargers should always have a ground fault interrupter, and transformer-based chargers should be of the isolation type.

Checking

This is not a paragraph about banking. It’s a paragraph about partnership. Whatever system you decide to use—continuity checking, verbal outcry, color coding, matching terminal pairs to a list, etc.—at least have one other human help you. It’ll make the conversion go faster, plus chances are you’ll find something that you alone might have overlooked. Speaking of chances, be sure your EV’s drive wheels are elevated the first time you hook up your batteries to your newly wired-up creation so it doesn’t accidentally “wander” through your garage door.