[cajunfj40]

cajunfj40 -- It's an excellent question and I support your asking it. You're looking for the known unknowns and the unknown unknowns, pace Rumsfeld.

Thanks, freebeard. I don't know what I don't know, so I ask, especially when research comes up short and I hit things like "50-1000VAC and 120-1500VDC are Low Voltage" in *international safety standards documents*.

I've always wondered about electric boats. Somehow they manage while immersed in an electrical conductor. Jack Rickard, on EVTV, compared the shore line for an aircraft carrier to a Tesla Supercharger cable. Pretty much the same thing.

Battery-electric boats have the same protections as battery-electric vehicles for other mediums: the high-current main propulsion circuit is isolated from the hull and other electrical circuits, so that any current leakage has to be due to at least 2 insulation faults. The current-carrying conductors are generally not touching the water, either, so there's nothing for the water to conduct. Of course, if you fill the battery compartment or motor compartment with water and it gets between terminals, you're going to see some current drain. If saltwater, quite a bit of it, and accompanying hydrogen/oxygen generation and explosion hazard. Freshwater (ie, not seawater) actually isn't all that great a conductor - it is the impurities that do the conducting. Ultra-pure DI water is used as a direct-contact-with-conductor coolant for laser power supplies. When it trips out for current leakage, the conductivity of the water's gone up too high and you have to drain and replace.

For ship to shore cables, you have IP-ratings for the connectors, proper insulation and environmental ratings for the cable itself, corrosion-resistant terminals, over-current and ground-fault protection circuits (commonly GFI's), etc. A GFI for an EV would probably be a good idea if you have a properly built battery box and you are running greater than 120VDC, though you might drive yourself batty chasing down all the current leaks after a few salt-road winters...

I would plan on IP-65+ or NEMA type 6+ or similar liquid-tight style conduit, glands and boxes for all wiring. UL listing for the common liquid-tight conduit is 600V or less, except in neon signs where 1000V is allowed. There may be higher ratings available. 600V might be "enough" of a boost over 350-400V to get where I want, though. that's ~417 amps for 200kw power output from an 80% efficient motor/controller setup. UL may not be the "correct" rating to go by for a car, though - they are looking from a building safety standpoint generally.