Hunter 356 - electrical issue when plugging in on the hard

[Knotallthere]

Hi all,

I’m wondering if someone can point me in the right direction with respect to this electrical issue we are having?

When I plug our Hunter 356 (2002) into the shore power connection on the hard it instantly trips our panel. Our boat is in the original OEM spec with just the two battery standard configuration. Everything is in the off position when I switch the panel on and has absolutely no load whatsoever.

When the boat is in the water plugged into the shore power pedestal on the dock everything works perfectly normal. This only started happening when my yard upgrade the outdoor outlets to new GFI’s a few seasons back, others in the yard seem to have no issue.

I’m using the standard pigtail connection to a high-quality extension cord. I’ve ruled out extension cords being the issue, as well as the pigtail as I’ve tried multiple different gauges of extension cords different pigtail fittings to ensure I eliminated if any of those had a weak point.

Any thoughts?

Best regards,

 

[Nichole340]

This happened to me last year at a slip in another marina. Mine was reverse polarity and the light alerting me to this was lit on my main panel. The odd thing was the next dock pedestal didn’t have the problem with reverse polarity when I plugged into that one.
Just thought I would mention this as it may be the situation with you as well.

 

[Don S/V ILLusion]

So everything works when plugged Into a pedestal but doesn’t when plugged into a shore receptacle?

Occam’s razor

 

[Knotallthere]

Thanks for getting back to me, as far as reverse polarity I haven’t seen any evidence of that, nor are any of the lights coming up on the panel to suggest that would be the case.

To answer the pedestal question everything is fine when I use my shore power cord and plug into the shore power connection on the dock when the boat is in the water; it is happening when the boat is out of the water stored on the hard and plugged in through a pigtail/extension cord into a standard outlet which is a GFI.

 

[shemandr]

Do you use the same pedestal/receptacle in the water and on the hard?

 

[Knotallthere]

Hi shemandr,

No, it’s a different outlet when we’re out of the water versus at the dock. Our yard has hundreds of boats in storage for winter and I’m the only one that seems to be having this issue.

 

[Rich Stidger]

Get an outlet tester and test the outlet that you are connecting to. If that is good, then test the end of the extension cord before the pigtail that connected to your shore power connector. There may not be a reversed connection, but there could be an open or high resistance connection somewhere.
If you are the only one with this problem, then it is likely that the fault is with your extension cord or pigtail. Or you have picked the only bad outlet in the yard. Or you have a black cloud over your head.

 

[shemandr]

Again, "Occam’s razor.” Thanks to Don for that expression I didn’t know. But in my training of diagnosis it was always said the simplest explanation is probably the correct one. That training has served me well.

 

[Knotallthere]

Get an outlet tester and test the outlet that you are connecting to. If that is good, then test the end of the extension cord before the pigtail that connected to your shore power connector. There may not be a reversed connection, but there could be an open or high resistance connection somewhere.
If you are the only one with this problem, then it is likely that the fault is with your extension cord or pigtail. Or you have picked the only bad outlet in the yard. Or you have a black cloud over your head.
View attachment 221551

Thanks Rich, I tried all the above and even bought brand new extension cords (heavy duty gauge). I also borrowed a pigtail from my neighbour who is not having any issues, and still have the same outcome.

 

[artboas]

Thanks Rich, I tried all the above and even bought brand new extension cords (heavy duty gauge). I also borrowed a pigtail from my neighbour who is not having any issues, and still have the same outcome.

I’m quite confident you have a hot to neutral reverse polarity at the shore outlet.
On the schematic, the neutral is bonded to ground. If the H & N are flipped, it will immediately blow the boat’s breaker.

 

[Rich Stidger]

Thanks Rich, I tried all the above and even bought brand new extension cords (heavy duty gauge). I also borrowed a pigtail from my neighbour who is not having any issues, and still have the same outcome.

So the outlet tester indicated that there were no faults?

 

[Knotallthere]

Hi Rich,

Yes, that is correct. There was a licensed technician hired under contract by the town that replaced the outlets a few seasons ago with new GFI‘s ever since then I’ve been having this issue.

Like I mentioned, there’s hundreds of boats in our yard and others are having no issue when plugged into the same outlets. I’ve tried multiple outlets throughout the yard and have the same result each and every time, as soon as I plug-in and turn the panel on it instantly trips.

I must have an issue with my boat but I’m just trying to figure out why it all of a sudden started happening and where the fault is. Does anyone believe that there’s something happening in behind my panel? Could anything there be causing this fault?

 

[jssailem]

I’ve tried multiple outlets throughout the yard and have the same result each and every time, as soon as I plug-in and turn the panel on it instantly trips.

All the other statements provided multiple possibilities. This says you have eliminated the new shore connection.

the outlet tester indicated that there were no faults

Yes, that is correct.

Going on the assumption that you tested the cord when plugged into the shore outlet and it tested “good” then the next place to examine is at the boat connection, working from there to the panel.

If you do not currently see smoke that is a good thing. The breaker is doing the thing it was designed to do.

I would not be concerned about the “sudden appearance”, it is enough that it occurred. Inspection of all the wires and connections between the power access plug and the panel breaker are going to help you narrow the issue.

Regarding “Sudden appearance” there are any number of possibilities. If you sail the boat is flexes and shifts things all the time. Most of the time everything stays in its place. Sometimes not. Corrosion occurs and screws get loose.

 

[Knotallthere]

Great advice thank you I’m going to follow the procedure that you recommended. I’m wondering if it could be a faulty breaker? The good news is this site sells them so I can replace it if necessary.

 

[Hello Below]

as soon as I plug-in and turn the panel on it instantly trips.

@Knotallthere you say "it" instantly trips. What is the "it" breaker? There will be 2 breakers inline with your shore connection. One will reside within 10' of your boat side connection and the other at the panel. Also do you have a galvanic isolator?

 

[heritage]

Galvanic Isolator trips Dockside Breaker

 

[artboas]

Great advice thank you I’m going to follow the procedure that you recommended. I’m wondering if it could be a faulty breaker? The good news is this site sells them so I can replace it if necessary.

Ok, this has me puzzled.
I’ve been looking at the Hunter schematics, but unclear which panel you have.
Is your main AC breaker a double breaker?
In any case, I might have a long shot solution
Inspect the wiring on the back your power inlet.

 

[artboas]

Ok, this has me puzzled.
I’ve been looking at the Hunter schematics, but unclear which panel you have.
Is your main AC breaker a double breaker?
In any case, I might have a long shot solution
Inspect the wiring on the back your power inlet.

question(s)
Have you always been at the same dock?
If you travel to other docks, does your shore power work ?

 

[Knotallthere]

Hi artboas,

I’ve had the same shore power connection in my slip for 5+ years. I haven’t gone to any transient slips in the last two seasons (day sailing only) since this started happening during the off season on the hard.

My boat has air-conditioning and everything functions perfectly normal when I’m in the water with my shore power cords plugged into the pedestal.

I hope to be able to get to the boat at some point this weekend to work on diagnosing what might be causing this issue. I picked up a non-contact voltage tester to see if I can find any wire issues as recommended in previous posts. I’m starting to wonder if the breaker itself behind the panel might have a weak point/fault.

 

[smokey73]

From your description, there are a lot of boats hooked into shore power where you have your boat on the hard. Is that correct? Is the Oakville you are referring to in Ontario, CT, MD or MO? I ask because if there are a lot of boats hooked up to shore power and drawing loads like heating and the like is it possible that the voltage is low at the pedestal you are hooked up to? If the wires are undersized feeding the pedestals and the loads are pretty large, then you may be seeing reduced voltage at the pedestal. In that case, the current for any given load would be higher and if the breaker is weak or marginal, it might be tripping on overcurrent. Just thinking outside of the box.

For instance, at my yacht club, we have two pedestals installed with 4 120 Volt 30A service connections on each pedestal. HOWEVER, only 2 of the 30A service connections are live at each pedestal. This is because when we installed the new, second pedestal, we calculated that the long wires from the clubhouse, down the pier, and to the pedestals were not large enough to carry the load for 8 30 Amp shore connections at the same time. To eliminate the possibility of dropping the voltage too much we only connected 4 of the total 8 available 30 A connections and left the other 8 not connected until when, or if, we upgraded the wiring size.