Shore power issue

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Well, where I come from, we put the zincs on AFTER the paint so we don't get paint on them....:)

And normally , a little pant here or there doesn't matter anyway.....but I guess the rubber doesn't matter either.
 
I normally make sure the area under the zinc is clean before it goes on and then tape the zincs before painting so I don't get paint on them.
 
I don’t know how everyone puts on bottom paint, but I don’t need a boot to protect my anodes from the bottom paint...
 
It is well worth the time, effort or expense to isolate nuetral from ground in the vessel, whether it was done purposely or not. If they are connected and it is a less resistant path to ground then the dock nuetral (corrosion on pedastals and such) then you could be drawing current through your underwater gear and ground system and other boats on the same leg of power could be drawing current through your boats ground too. This is if dock is not GFCI protected.
 
if you are tripping the GFIs then you are leaking more that 30milliamps. To resolve the leakage issue, you will need to find a current clamp meter that can measure milliamps and a home made adapter cable to give access to the neutral and line wires inside your shore cable. you will need to place the current clam around (neutral + Hot) where it should be reading closer to 0mA (lower than 30mA). with the clamp in place try to turn ON your individual system to find the culprit one. repeat the test on the second shore cord.
Most failures are simple to fix and are usually a swapped ground and neutral wires(or shorted) on a specific system or an outlet when used.
Good hunting
 
There are other ways that don’t require a clamp on meter and an adapter to split out the shore power wires. I did mine with an extension cord with a GFI outlet on it.
 
A GFCI monitors the amount of current flowing from hot to neutral. If there is any imbalance, it trips the circuit. The GFCI senses a mismatch as small as 4 or 5 milliamps, and it can react as quickly as one-thirtieth of a second. If you have a current mismatch on any of the leads the GFCI will trip.
 
fgarriso said:
A GFCI monitors the amount of current flowing from hot to neutral. If there is any imbalance, it trips the circuit. The GFCI senses a mismatch as small as 4 or 5 milliamps, and it can react as quickly as one-thirtieth of a second. If you have a current mismatch on any of the leads the GFCI will trip.
Click to expand...

Household GFCIs are usually around 6 mAmps. The ones on the docks are 30 mAmps for individual slips and 100 mAmps if they serve a dock..
 
Boatcrazy said:
Just to clarify....the zincs I'm referring to are rectangular, typically about 3"x6" and about 2" thick, and have an exposed steel center portion with 2 bolt holes. They fit into a shallow well molded into the hull. The rubber "boot" only covers the outside portion of the back side and approx 0.5" up on the 4 sides. And, as I've written and had it explained to me, the idea is to insulate the back and sides from slopped over antifoul paint in the zinc well. There's still plenty of zinc surface exposed to seawater, and nothing interferes with the bolt/zinc connection. Enough said!
Click to expand...

The rubber backing pad is not unheard of, Nordhavn uses them, see attached, however, they are by no means common, in fact they are the exception. I don't believe they are necessary, but probably do no harm either.

Interestingly, in this case, the anti-fouling is cut back from the anode, so no contact even with the rubber pad, and a accretion with a hard outer surface and soft inner section has formed between the rubber pad and the hull. I have yet to conduct a reference electrode test on the hull, however, I'll share my findings when I've done so. No corrosion or abnormal anode consumption was observed.
 

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Comodave said:
If you only have one 30 amp inlet then I would unhook it from shorepower and turn everything off. Then ohm between neutral and ground. It should be open or no connection. If it is open then turn on circuits one at a time and see if there is a connection on any of the circuits. If there is any connection then some current can flow back on the ground wire. No current should be on the ground. If there is any then the GFCI will trip because it is looking for the exact amount of current returning on the neutral that is going out on the hot wire. If the imbalance is more than 30 mAmps for docks with individual GFCIs or 100 mAmps for docks that have one GFCI for the whole dock then the GFCI will trip. There should be no connection between the neutral and ground except at the source of power, in this case the shore power. If you have a genset then the connection between neutral and ground will be inside the genset. If you find a circuit that has a connection between neutral and ground then you know where to start looking for the problem.
Click to expand...
To the layman can you explain more about conducting this test?
Where would I ohm between the neutral and ground? At the shore power plug in receptacle?
Thanks
 
jclays said:
To the layman can you explain more about conducting this test?
Where would I ohm between the neutral and ground? At the shore power plug in receptacle?
Thanks
Click to expand...
OK, the power is off, shore cord disconnected, inverter off.

You can go to main panel across GND and Neutral
You can stick the prongs in any wall outlet GND and neutral
You can leave shore cord connected to boat and go between GND and neutral on the male prong end of the cord.
 
Soo-Valley said:
Any idea what the issue was that was bypassed.
Click to expand...

He didn't explore it past simply bypassing the galvanic isolator. We're in fresh water and have been told the isolator is not needed in fresh water. I don't know if that's true or not. We are all on 5 mA gfci breakers now so there isn't going to be much current leaking anywhere I guess.
Hawk
 
Galvanic idolaters are about DC current not AC current. They stop the DC current from migrating trough the ground wire and causing electrolysis. Since fresh water is un conductive there is no path and hence no electrolysis.
 
Hawkshaw1 said:
He didn't explore it past simply bypassing the galvanic isolator. We're in fresh water and have been told the isolator is not needed in fresh water. I don't know if that's true or not. We are all on 5 mA gfci breakers now so there isn't going to be much current leaking anywhere I guess.
Hawk
Click to expand...

The 5 mAmp GFCIs are household use. The marine ones are 30 mAmp for individual slips or 100 mAmp if used on the whole dock. I do have 5 mAmp ones on my home dock though.
 
tiltrider1 said:
Galvanic idolaters are about DC current not AC current. They stop the DC current from migrating trough the ground wire and causing electrolysis. Since fresh water is un conductive there is no path and hence no electrolysis.
Click to expand...

Maybe, but I was asking why it needed to be bypassed to solve what issue. Their problem was solved by bypassing, so was the GI causing it or was the issue solved by re routing wires which had the issue within.
Solved is good, knowing what was broken then fixed priceless.
 
Generally speaking, bypassing a GI, not something I recommend, should have no effect on a tripping GFCI or ELCI, However, if that GI is of the legacy 'self-test' variety (which are now obsolete, the latest ABYC GI standard does not mandate those, instead 'fail-safe' GIs are acceptable) absolutely can cause a ground fault device to trip.
 
What Steve said. The self testing galvanic isolator that came on our Mainship was one of the problems that would trip the breaker. The other was a neutral bus shared between the shore power and the inverter.
 
Rhodewaves said:
I have a galvanic isolator , could that be the issues
Click to expand...

If it is an older ProMariner with the test panel, yes indeed as the test circuit will induce a bit of mismatched voltage across the neutral and hot lines. See the ProMariner website for their take on this older model.
 
porman said:
What Steve said. The self testing galvanic isolator that came on our Mainship was one of the problems that would trip the breaker. The other was a neutral bus shared between the shore power and the inverter.
Click to expand...

That seemed to be what my friend's issue was and it was wired as you described.

We were required to update our breakers by state law, in addition to the code changes.

The 30mA are on backorder for 3 months and only come in 50 Amp for the boxes that we have and are about $200 higher so we have the 5 mA for now which is not ideal.

I would love to know if the 30mA trip GFIs are that much more forgiving.

Hawk
 
It just depends on the size of the leakage. I have household GFIs on our dock that are 6 mAmp. Our last boat would trip them just by plugging it in until I rewired the boat, then no problems. They are also much cheaper than the 30 mAmp ones.
 
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