Boat dock grounding and NEV

[dbchamblee]

To minimize the effects of neutral-to-earth voltage (NEV) at boat docks, I heard it suggested to install only low voltage DC equipment (lighting, boat lifts, etc.). The thinking is since you don't have AC run to the dock, you don't have to ground metal parts which prevents the neutral voltage from being transferred to the metal parts.

Would it have to be run off batteries or PV? Could you have an AC power supply as long as it was on shore?

Thoughts?

 

[kwired]

If the supply is totally isolated from anything with continuity to the utility neutral you shouldn't have any NEV issues. An AC to DC power supply powered by utility power has some risk of some sort of interconnection of grounded conductors especially if the DC system is grounded.