GFCI Problems on a Tiny Houseboat

fallguy, I got a response from Sungoldpower saying; “When the inverter is turned off, the inverter is in a power-off state, and the 120V shore power grid is not connected to the inverter output”. Thus, wiring a ByPass circuit as reflected in the diagram I last sent you yesterday would not have a functioning ground connection. Based on that, I redesigned the wiring diagram (attached-Highlighted in Yellow) adding an “all three wires” circuit through an “Always OFF” switch between my ELCB input and my CFCI input terminals. Will this work to serve as a ByPass circuit from the Shore/grid receptacle and the boat’s 120v AC LOAD circuits so I can maintain my 12v Wet HOUSE & starting batteries (using a 12v AC Maintainer) and 120v AC refrigerator when the Solar Panels, Inverter, and Lithium battery are disconnected at their individual circuit breakers?

I also, per your advice, removed the connecting wire between the Earth Ground Bus Bar and the negative terminal on the HOUSE battery.

Do you see any problems wiring the entire solar system as shown or the proposed ByPass circuit? As always, Thanks. Jim

 

What are you doing?

I never said to remove the ground from the battery. The house battery does not function without it’s ground.

 

Fallguy, I am terribly sorry, as it seems that I have misled you. Before I started adding the solar system to my boat, it used a 12v DC HOUSE battery to power the interior lights and the water pump for the sink. It has a second 12v DC starting battery which powers its running lights and motor controls and gauges. These two DC batteries are connected through a selector style switch to allow switching, in an emergency, to either battery for starting. I have not included any of those DC system items or their wiring in my wiring diagrams because I have kept that DC system completely separate from the solar panels/inverter/Lithium battery 120v AC system I have installed to power the newly installed 120v AC circuits and AC appliances.

Till this date, the only connection between the DC and AC systems has been running an earth ground wire from the AIO inverter’s housing/case to the negative terminal of the starting battery so there would be a ground path, while at sea, to the water (earth ground). I have since, added an, always OPEN, earth ground wire from the AIO casing directly to the outboard motor’s lower housing, thus, eliminating the need to connect the AIO with the negative terminal of the starting battery, which you said, might be isolated/disconnected when the boat is NOT underway.

I hope this explains why I removed the ground connection between the AIO' chassis and the starting battery’s negative terminal. Doing so, has no impact on the boat’s existing DC systems, HOUSE or Starting. Jim

 

Galvanic isolator and ELCI precedence https://www.boatdesign.net/threads/galvanic-isolator-and-elci-precedence.38087/

 

The neg term of the start battery shares a node with the frame of the ob and ergo the lower unit. There is no need for an additional wire. Not sure I follow the logic here.

ALL of the grounds on the boat ought to be shared. So, for your boat, no floating grounds exist.

AND, all metal components underwater need to be part of this grounding system.

You can float a lightening protection system that is not below waterline afaik.

 

fallguy, I added the extra 4 AWG wire connection directly from the AIO chassis to the OB because, I read that the earth ground wire should be only one wire size smaller than the Lithium battery wire (2AWG), my OB is mounted to the boat on a wooden clamping area (i.e., isolated), and I was getting an OPEN Ground signal at my 120v AC outlets when their source of power was only the AIO (i.e., not plugged into grounded shore power). For ground testing purposes, because the boat was on a trailer, I also, ran a temporary wire from the OB to a driven ground rod/stake, so the OB would be connected to the earth.

By employing the reflected Earth Ground Connecting Bus Bar, I believe all of my grounds are shared.
By “all metal components underwater need to be part of this grounding system”, to make sure, should I also run an earth ground wire to the metal pontoons?

As for Lightening, I have thought about, installing a 5/8” D solid copper rod to the side of my boat, extending above the boat by around 2 feet and running into the water for around 2 feet. Do you think this would provide a safe lightening rod for the boat? Jim

 

The pontoons need to be continuous to the grounds.

Please read the links I offer.

https://www.bluesea.com/support/art..._Interrupters_[GFCIs]_to_make_your_boat_safer.

 

It is important to ground the hulls, but the hulls ought never be made into a ground node, to be clear. This means you NEVER make the hull into a ground wire for a device. We don’t want current passing through the hull(s).

 

fallguy, I added the extra 4 AWG wire connection directly from the AIO chassis to the OB because, I read that the earth ground wire should be only one wire size smaller than the Lithium battery wire (2AWG).

My OB is mounted/bolted to the boat at/on a wooden clamping area (i.e., isolated I think), and, when employing a Plug In 120v AC Circuit Tester, I was getting an OPEN Ground status at my 120v AC outlets when their source of 120v AC power was only the AIO (i.e., not plugged into grounded shore power). When Plugged into the grounded shore power, the tester reflects “Correct Wiring” with no OPEN Ground.

Do you have any suggested diagnosis paths I should take, for earth ground testing while only the AIO is powering my outlets? Because the boat is on a trailer, I also, ran a temporary wire from the OB housing to a hammered in ground rod/stake, so the OB should be connected to the earth. I got continuity between the negative terminal of the starting battery and the rod I drove into the ground as a ground rod. Jim

 

fallguy, thanks for the link. I read the bluesea article about a month ago and then ordered both the ECLI and the GI and installed both. Because the ELCI only involves passage for the Hot & COMMON wires, it seems not to make much of a difference which is first, so I installed the GI (applies to Ground wire only) and ELCI side-by-side about 8 feet after the shore receptacle.

When you said “Pontoons should be continuous to the grounds”, I ran a continuity test to see if they and the OB were ground connected. It came back negative continuity, so, should I connect them with a wire?

 

You check the hulls for continuity to the ground bus. The case of the OB should be connected to the starter negative and that should tie back to the ground bus.

 

There is some argument for and against tying the hulls to the grounding system.

If you have a raw water intake in your hull, say bronze, and an aluminum hull; those two need to be electrically connected and then to an anode and that bonding system tied to ground bus is my approach.

@Ike may be willing to offer some insights

 

My boat is strictly an aluminum pontoon boat. Have continuity between OD and starter negative & ground bus, will check with pontoons today. Jim

 

Let’s recap briefly.

All your AC electrical outlets in a boat should be GFCI after an ELCI that is near the shore power inlet. This means all of them. If you buy a window air conditioner that has a GFCI male plug and you plug it into an AC circuit; you are stacking Gfcis and results can be spurious or uncertain.

You are choosing to disconnect the solar system when away and rely on shore power. I am assuming then your fridge is AC powered.

Did you get the new Air Conditioner?

Any chance you’d share a picture of your tiny houseboat? We all love boats here on the forum.

 

GFCI does not need a working ground wire
GFCI detects electric current flow imbalance

Current going in must equal current going out of a circuit, within 5 milli amps
With GFCI the ground does nothing
Ground though is always considered a normally non current carrying wire, it is a safety ground only which is still a good idea to have it.

If a GFCI sense unequal currents, then current is escaping the wiring path and that creates a shock hazard, so it trips off the current flow, which is a good thing.

I suppose trouble shooting current leakage should begin with isolating circuits from others and getting something GFCI functional, then add on other circuits.


Can You Hook Up A GFCI Without A Ground Wire? (Step By Step) - PortablePowerGuides