Two Amp Feedback to Shore Power Cable - Help!

[daddle]

I propose nobody should care "which way" the current is flowing*. It might be AC, in which case it's flowing both ways. And if it's "flowing on" to the vessel by the ground wire it is certainly "flowing off" some other way. Thru the water I'd predict. Your procedure might be valuable for investigating proper sacrificial anodes, but not a fault that causes an arc.

Interesting problem this is. And we are lacking the simplest data.

* If one gets electrocuted, does it make a difference if the current is flowing out of your ring finger or into it?

[Christian Van H]

Originally Posted by daddle

* If one gets electrocuted, does it make a difference if the current is flowing out of your ring finger or into it?

Some would argue that if there's a ring on that finger, your life is already over...

[Fishman_Tx]

HAH! That's true!

[s/v Jedi]

Okay, let me make it simpler: if the OP owns a Fluke and has enough knowledge, he wouldn't have posted the 1st post in this thread. So he really should find or hire someone who is qualified to test this. I think the matter and possible consequences are too big to try out some things himself even with some sound advise as given in this thread.

cheers,
Nick.

[denmanislander]

Well, I do have some electrical background but am new to the big boat scene and was looking for ways to positively figure out what the problem was. However, unfortunately (or fortunately!) I have a job and can't get back to the boat right away ( it is on a different island at a government wharf). I will use the multimeter this weekend and go through all of the advised steps. Thanks for the hints! As to hiring someone to look at this, two ferries and a 1/2 hour drive from the nearest town at $$$/hour means I wouldn't be able to afford to go out in the boat this summer!

[denmanislander]

OK! I have been to the boat, shore power disconnected, here is what I found:
My ground terminal to marina power enclosure (aluminum box) = 0.6VAC/ 0.4 VDC
My ground terminal to seawater = 0.01 VAC/ 0.7 VDC
Marina power enclosure to water = 0.6 VAC / 0.275 VDC
From Charlie's suggestion @#27, current apparently is flowing from my boat (although I don't understand how what I measured indicates this!)with a reading of .4 VDC
Marina ground to water = 0 ohms
My ground to water = infinite resistance

On my boat:
Main AC breaker ground to AC ground bus is infinite ohms
DC neg bus to AC ground bus = 0 ohms
Generator/Shore power switch switches two sets of black and white wires - no bus connections and it makes no difference to voltage readings what position this is in.
These voltages don't seem high enough to say anything definite, but I will await all your welcome replies.

[sailvayu]

The reading to the shore ground are normal back ground voltage, do you have a galvanic isolator in your ground, if so it might not be working.

Readings to the water are meaningless unless you are using a half cell as a standard.

The breaker should NEVER break the ground wire so not sure what you are saying when you say ground to breaker ground. If the breaker has the green wire on one of 3 terminals this is a problem.

I would start with a 3 light tester and check polarity first off.

Did you read my article it really will help if you do as many of those tests as you can.

So far not enough information to make a guess, sorry need more clues

let me know what you find with a 3 light tester

Good luck

[denmanislander]

I forgot to add that I ran the generator and checked all the 120 outlets- all are fine, no faults.

[rtbates]

On your boat are the AC neutrals (white wire) connected to the AC ground (green wire)? I won't get into a pissing contest (it always does) about whether they should or should not be connected at the boat. IF they are, I suggest you seperate them and see what you see...