Dock Stanchion GFCI breakers and your boat

If I'm reading all of this correctly (thanks for everyone's input!), on my older ('92) boat, I should install an isolation transformer to be able to use the newer shore power pedestals, and then focus on GFCI/safety issues in the boat itself. Yes?
Nope - fix the boat if you are tripping the safety device. Your boat regardless if it has an isolation transformer or not should not be leaking AC current anywhere. If your boat is correctly wired and operating properly it will not trip the shorepower GFCI; isolation transformer or not.
 
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If I'm reading all of this correctly (thanks for everyone's input!), on my older ('92) boat, I should install an isolation transformer to be able to use the newer shore power pedestals, and then focus on GFCI/safety issues in the boat itself. Yes?

That's exactly what I need to do. Unless I can correct everything over the winter. But I can tell you from experience this past summer at a few places. The voltage is also lower, meaning they provide 208v which is what most isolation transformers want as they can also boost the voltage by moving the center tap (neutral). Some like Victron and Charles can do that. Of course it's best to have 220/240 supplied but it seems it varies quite a bit. I have been seeing this with Safe Harbor marina's and new floating docks.

I was on a trip this past August with three other boats and one of the SH marina's we were at had this issue and two of the other boats could not get plugged in. I was lucky and took the only stanchion that did not have GFCI outlets. As a result we went and anchored out for the night and moved on a day early. The other two boats were Regals and 2007/8 but no isolation transformers.
 
Electricity is not my strong suit, but after we had our marina totally updated with new docks, power, water, everything, tripping the gfci on the docks was a nightmare with 1100 slips. I learned a few things but nothing close to Tom’s knowledge. Like he said earlier, check the generator and the appliances.
We had 2 boats on our dock that were throwing the gfci’s. One was a genny problem and the other was a leaky microwave.
 
I do have one question from the 50Amp perspective and cannot get clarification on this. All I have ever read states both 110v legs must draw equal current to not pop the breaker. Is that literal or are they just referring to each leg independently referenced to neutral? I have just guessed it means both legs independently referenced to neutral because otherwise it's always going to pop the breaker.

Sorry Orlando, I didn't pick up on what you are asking here.
What you are talking about is load balancing. For a marina in whole to operate properly they try to balance all of their loads across the utility phases coming in; unbalanced loads equate to higher utility costs.
So, on a boat - the design of the boat entails limited size in main power conductors, switches, connections, etc to enable the lowest cost and weight. To optimize sizing the designers try to balance the load (current) across all of the supply feeds. To have an imbalanced load will not necessarily trip any dual pole breakers unless one leg exceeds the circuit breaker rating. Unbalanced loads on a generator is entirely another story; to have excessively unbalanced loads on the generator's windings causes vibrations, higher than normal heat in the windings, and a host of other undesirable effects.
 
That's exactly what I need to do. Unless I can correct everything over the winter. But I can tell you from experience this past summer at a few places. The voltage is also lower, meaning they provide 208v which is what most isolation transformers want as they can also boost the voltage by moving the center tap (neutral). Some like Victron and Charles can do that. Of course it's best to have 220/240 supplied but it seems it varies quite a bit. I have been seeing this with Safe Harbor marina's and new floating docks.

I was on a trip this past August with three other boats and one of the SH marina's we were at had this issue and two of the other boats could not get plugged in. I was lucky and took the only stanchion that did not have GFCI outlets. As a result we went and anchored out for the night and moved on a day early. The other two boats were Regals and 2007/8 but no isolation transformers.
208 volt is entirely another thing. The cheap way for a marina to power docks is to simply use two legs of the utilitiy's 3 phase power industrial supply from the transformer rather than installing the additional split phase transformers. 3 Phase power is actually three Hot conductors all out of phase by 120 degrees. What this does is never allow simultaneous sine wave peak to peak voltage differential. Each voltage peak is aligned with another phase off their peak. Take a look at this for 3 phase.
harmonics-distortion.png
 
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Sorry Orlando, I didn't pick up on what you are asking here.
What you are talking about is load balancing. For a marina in whole to operate properly they try to balance all of their loads across the utility phases coming in; unbalanced loads equate to higher utility costs.
So, on a boat - the design of the boat entails limited size in main power conductors, switches, connections, etc to enable the lowest cost and weight. To optimize sizing the designers try to balance the load (current) across all of the supply feeds. To have an imbalanced load will not necessarily trip any dual pole breakers unless one leg exceeds the circuit breaker rating. Unbalanced loads on a generator is entirely another story; to have excessively unbalanced loads on the generator's windings causes vibrations, higher than normal heat in the windings, and a host of other undesirable effects.

Thanks Tom. You answered what I was trying to ask. I have two independent panels and they are balanced, sort of. I say sort of because one panel has a lot of devices that are not always on. But when on the panels are balanced, it just worked out that way when I was calculating the loads. Sea Ray originally had it unbalanced even worse then I do now. When I replaced my electric panel a few years ago I added a few new breakers and ran new lines for them, which is why I am very surprised that I have an issue on one of those lines now.
 
208 volt is entirely another thing. The cheap way for a marina to power docks is to simply use two legs of the utilitiy's 3 phase power industrial supply from the transformer rather than installing the additional split phase transformers. 3 Phase power is actually three conductors all out of phase by 120 degrees. What this does is never allow simultaneous sine wave peak to peak voltage differential. Each voltage peak is aligned with another phase off their peak. Take a look at this for 3 phase.
harmonics-distortion.png

Yes that is exactly what SH is doing and is a real issue for boat's that are safe with no GFCI issues but still require 220v. Thank you for explaining that. My expertise has always been in the digital realm and communications. I am quickly being schooled as a result. I appreciate all of your input. You have solidified most of what I have learned in the past few years because of this situation and added to the rest of what I was missing. When it comes to phases and transformers that is a black hole for me, but this makes perfect sense. Thanks
 
Here is another thing - a marina that has full ground fault protection will have few electrolysis problems on the boats in the marina. Everybody is forced to clean up their boat's electrical systems. I like it.
 
Keep in mind the reason NEC rules were tightened up for marinia GFCI is life safety. Ground Faults thru the water were discovered to be the root cause of many at marina drownings. The drownings were secondary to electrical induced paralysis.

For years now people have been warned not to swim around boats in marinas. But people can just fall in. And still others will check props or scrub bottoms. This was very risky.
 
Keep in mind the reason NEC rules were tightened up for marinia GFCI is life safety. Ground Faults thru the water were discovered to be the root cause of many at marina drownings. The drownings were secondary to electrical induced paralysis.

For years now people have been warned not to swim around boats in marinas. But people can just fall in. And still others will check props or scrub bottoms. This was very risky.

Yeah it was once only prevalent around lakes and fresh water and wasn't really noticed around salt until the boating numbers increased and deaths along with it. And now with every "Joe" buying a boat and knowing they know everything, because how hard can this be right? Then find themselves in a bad situation they can't get out of. I have seen people dive right in at my marina to fix something and give it no second thought.
 
So I couldn't let this situation go. I dove into this today while it was raining and found a single wire run that had 1.0 ohms between neutral and ground. Took that off the neutral bar and now I have zero leakage current with everything on and running. Now this is the scary part, I can't trace that wire run to find out where it goes. So now it is disconnected and everything works. Even tested all the outlet's with a Fluke 120 GFCI tester.

This white neutral wire is an original wire that has not been replaced yet. Tried tracing it out and it goes into a bundle of wires I can not reach nor get too without destroying the built in bar area that Sea Ray originally built. So after five hours of unscrewing and testing wires it was almost the very last wire I had to pull to test. Going to try and open up that bundle blindly and see if I can get to the jacketed wire itself and trace the the other two wires back up to the panel. I am hoping this is the old auto bar that was removed by the PO and the wires are dead ended.
 
So I couldn't let this situation go. I dove into this today while it was raining and found a single wire run that had 1.0 ohms between neutral and ground. Took that off the neutral bar and now I have zero leakage current with everything on and running. Now this is the scary part, I can't trace that wire run to find out where it goes. So now it is disconnected and everything works. Even tested all the outlet's with a Fluke 120 GFCI tester.

This white neutral wire is an original wire that has not been replaced yet. Tried tracing it out and it goes into a bundle of wires I can not reach nor get too without destroying the built in bar area that Sea Ray originally built. So after five hours of unscrewing and testing wires it was almost the very last wire I had to pull to test. Going to try and open up that bundle blindly and see if I can get to the jacketed wire itself and trace the the other two wires back up to the panel. I am hoping this is the old auto bar that was removed by the PO and the wires are dead ended.
Yea!
Does that conductor go into some triplex? If so what, if anything, does the black wire land on?
 
Yea!
Does that conductor go into some triplex? If so what, if anything, does the black wire land on?

That is exactly what I can't find and is my next step in finding out. It's very strange that everything is working and I now have zero leakage current with everything on, hot water heater, cook top, microwave everything and that this one wire was the entire issue.

The issue is I can't trace the white back to the wire bundle just yet. I have to remove somethings to get my arm in there and try and blindly find the single run and then trace the black and green to where ever they are connected. A job for later in the week.
 
That is exactly what I can't find and is my next step in finding out. It's very strange that everything is working and I now have zero leakage current with everything on, hot water heater, cook top, microwave everything and that this one wire was the entire issue.

The issue is I can't trace the white back to the wire bundle just yet. I have to remove somethings to get my arm in there and try and blindly find the single run and then trace the black and green to where ever they are connected. A job for later in the week.
If you had to have a problem, that is one I could live with. It's awesome that the boat is electrically solid now.
 
If you had to have a problem, that is one I could live with. It's awesome that the boat is electrically solid now.

Thank you, I have worked hard at trying to get it that way and was surprised when I found I had an issue. I am just leery of puling a neutral wire without knowing where it leads too. But as you said, I can live that if I have too.
 
@ttmott - Tom thank you so much for sharing this. If we got into a Computational Fluid Dynamics discussion of supercritical wing design, I cold participate, but OMG, I am so lacking in EE knowledge! I blame myself, but I would love to put the blame on Vanderbilt and Princeton's Engineering Schools (to no avail!!).

You make me realize how much I do not know...
Carter, don’t sell your self short. Without your knowledge we would still be carefully measuring No-Flex instead of liberally pouring in Carter’s Poopy Powder!
 
So the point in my prior question is…
If a shore power gfi fault occurs it can be because of any electrical device onboard be it an outlet, refrigerator, etc. Additionally, sufficient moisture present between 2 male prongs on a plug can cause a gfi fault. Therefore troubleshooting and identifying the “problem” can be laborious…
Not necessarily - Don't confuse a circuit breaker which protects from over-current with a GFCI which protects from current leakage.
If moisture (salt water), for example, was trapped between the hot and neutral prongs then the current would go up and if enough would trip the circuit breaker but would not trip the GFCI. Alternatively, if the moisture was between the ground prong and either one of the hot or neutral conductors then current would be "escaping" from the circuit to ground and that would trip the GFCI but not the circuit breaker.
 
So I couldn't let this situation go. I dove into this today while it was raining and found a single wire run that had 1.0 ohms between neutral and ground. Took that off the neutral bar and now I have zero leakage current with everything on and running. Now this is the scary part, I can't trace that wire run to find out where it goes. So now it is disconnected and everything works. Even tested all the outlet's with a Fluke 120 GFCI tester.

This white neutral wire is an original wire that has not been replaced yet. Tried tracing it out and it goes into a bundle of wires I can not reach nor get too without destroying the built in bar area that Sea Ray originally built. So after five hours of unscrewing and testing wires it was almost the very last wire I had to pull to test. Going to try and open up that bundle blindly and see if I can get to the jacketed wire itself and trace the the other two wires back up to the panel. I am hoping this is the old auto bar that was removed by the PO and the wires are dead ended.
“Abandoned in place “ wires could most definitely be a cause. If the PO cut off the black in the panel but left the neutral and ground. Then at the auto bar just cut the end off. Any moisture corrosion or a single strand of the neutral and ground touching would be a fault.

Is it easier to get to where the auto bar was?
 
“Abandoned in place “ wires could most definitely be a cause. If the PO cut off the black in the panel but left the neutral and ground. Then at the auto bar just cut the end off. Any moisture corrosion or a single strand of the neutral and ground touching would be a fault.

Is it easier to get to where the auto bar was?

I am hoping these were from the auto bar, but I need to trace the neutral to find the hot and ground. But no it's not easy at all to get to where the auto bar wires are. There exactly where the bar is and where the wires disappear behind it. Coming in from the other side behind the steps is where all of the wires come in to the panel, but there is about two feet of the bar that stops it from being accessible. Not to mention it is all bundled and wrapped in wire harness covering and wire tied.
 

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