BoatHowTo · video

What this video covers

Nigel Calder explains why a boat running a 230V inverter off a solar battery bank — with no shore power connection — still needs proper AC grounding, and what can go wrong without it.0:25

Inside virtually all marine inverters is a relay that, in invert mode, connects the neutral side of the AC system to the AC grounding side.0:52 That neutral-to-ground bond is the safety path that trips protection devices when equipment develops a fault to its case. Without it, faulted equipment can remain fully functional while energized to the touch; a person who contacts it becomes the fault path and can be electrocuted.3:13 Shore-power inverters lack this internal relay because the neutral-to-ground bond is made at the panel or generator elsewhere in the system — making a marine-rated inverter essential on a boat.1:09 Calder adds a second risk: many modern marine inverters allow that relay to be disabled in software, so owners of newer units must verify the relay is enabled.1:32 In pass-through mode the relay correctly opens, transferring the neutral-to-ground bond to the dock or generator source.1:57

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