Boats on hard ground so lets talk grounds

[anemoneii]

My boat has no ground wire for the 110V, the wiring diagram shows a 10 gauge black wire running from the ground buss bar in the panel to the engine block.
We all know that 12v DC grounds are black in cars and boats, but should the 110v AC ground be Black as the diagram shows (always default to the manufacturers instructions?) or Green?

[Garffin]

As long as that engine ground is not part of the return circuit. you should be ok there but yeah use a multi meter when you don't know for sure don't go by the wires colors nor some manufactures guide. If your not sure check it before you wreck it. Dan

[anemoneii]

By return you must mean neutral? Th neutrals are white as they are on land. They are seperate.

[mitiempo]

anemoneii
I'm not really sure what Garffin is trying to say. Are you saying that all your onboard AC circuits are 3 wire but there is not a ground to the negative bus (or engine block)? If the answer is yes I would use green so it can be identified easily in the future. A black wire to the negative bus would look like it came from a DC source. Do you have or are you going to install a galvanic isolator?

[BubbleheadMd]

Originally Posted by mitiempo

anemoneii
I'm not really sure what Garffin is trying to say. Are you saying that all your onboard AC circuits are 3 wire but there is not a ground to the negative bus (or engine block)? If the answer is yes I would use green so it can be identified easily in the future. A black wire to the negative bus would look like it came from a DC source. Do you have or are you going to install a galvanic isolator?

MiTi has it right- Black is hot, white is neutral and green (or bare) is ground.

In household AC outlets, the bare copper wire goes to the green screw, black goes to the brass screw, and white to the silver screw. So remember this phrase when wiring up 110V 60Hz AC switches and receptacles: "Black to brass will save your ass, and ground is green as grass".

This is for shore power right?

[xsboats]

This is right for shore power except that there is no ground on board. All grounds are wired to the panel and then connected to the ground on the dock. There should be no ground for the shore power hooked up to the engine block, keel bolts, dynaplate, or any other grounding point commonly used in the d.c. system.

[anemoneii]

Originally Posted by mitiempo

anemoneii
I'm not really sure what Garffin is trying to say. Are you saying that all your onboard AC circuits are 3 wire but there is not a ground to the negative bus (or engine block)? If the answer is yes I would use green so it can be identified easily in the future. A black wire to the negative bus would look like it came from a DC source. Do you have or are you going to install a galvanic isolator?

My boat is kept on a mooring, if I spend 10 hours a year plugged into the Yacht Club dock that would be alot, I don't see the need for one.

[anemoneii]

Originally Posted by xsboats

This is right for shore power except that there is no ground on board. All grounds are wired to the panel and then connected to the ground on the dock. There should be no ground for the shore power hooked up to the engine block, keel bolts, dynaplate, or any other grounding point commonly used in the d.c. system.

You are making this conversation interesting, I have Don Casey's book, Sailboat Electrics Simplified, and he shows the ground hooked to the engine, also the wiring diagram for my boat shows one (although it is not there). The Engine is certainly grounded to the 12v DC system.

[tommays]

Well

What happens If you supply some 110 from and inverter YOU still need a ground

They have been wiring the DC in RED/YELLOW and the AC in BLACK/WHITE/GREEN to resolve this issue in newer boats

[nickmerc]

The ground wire should be green as stated above. It should also be connected to both the ground pin on the AC adapter and the engine block. When doing this try to keep all grounded and bonded connections in a star pattern. This means a single wire from each device and engine to the main ground bus. Basically, you do not want to have one device/thru-hull in series with another device/thru-hull.
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Cyaraa