dock GFCI trips out

Several of the responses here indicate that the responder has not read or has not understood all the information posted by the original poster.

For example, he stated that with nothing on the boat powered on, the breaker still trips. It's not the fact that it's a 20 amp breaker that's causing the problem. It's not an overload. He also stated that the dock pedestal has a standard three wire twist lock receptacle.

Several people have suggested having the marina replace the GFCI breaker with a non-GFCI breaker. Well, that's the obvious, but the marina may not be willing to do that for whatever reason. He doesn't own the marina, he only rents a slip there.

GSENT posted that the reverse polarity lights on the boat may be causing the GFCI breaker to trip. That's a possibility because reverse polarity indicators are wired into the circuit differently than any other appliance or device. The easy way to find out is to disconnect them temporarily. I didn't have this problem when I kept a trailered boat at home on a GFCI breaker, but that doesn't mean it's not a possibility worth looking into.
 
Thanks to all who have posted so far and to rawidman for clarifying several important points.

The comment about the current in the reverse polarity indicator lamp possibly causing the GFCI to trip is very interesting. I don't have an indicator that is marked "reverse polarity", but I do have an indicator marked "shore power". I'm assuming this just indicates that my shore power cord is connected, but then I can get the same information by looking right above at the voltmeter. However, the current through this indicator lamp may be causing the GFCI to trip. When I am at the boat this weekend I will disconnect this bulb and see if that eliinates the GFCI tripping. Good input!! Keep it comeing, I'm learning a lot.

BY the way, I have an indicator lamp for each of the breakers on my main panel. Could each of these be adding leakage current causing the GFCI to trip?
 
quote:
Originally posted by PatSea

Thanks to all who have posted so far and to rawidman for clarifying several important points.

The comment about the current in the reverse polarity indicator lamp possibly causing the GFCI to trip is very interesting. I don't have an indicator that is marked "reverse polarity", but I do have an indicator marked "shore power". I'm assuming this just indicates that my shore power cord is connected, but then I can get the same information by looking right above at the voltmeter. However, the current through this indicator lamp may be causing the GFCI to trip. When I am at the boat this weekend I will disconnect this bulb and see if that eliinates the GFCI tripping. Good input!! Keep it comeing, I'm learning a lot.

BY the way, I have an indicator lamp for each of the breakers on my main panel. Could each of these be adding leakage current causing the GFCI to trip?

Click to expand...

Normal lamps won't trip a GFCI breaker.

As I recall, the reverse polarity lamps work like this:

The green or "OK" lamp connects from the "hot" conductor to ground. The red or "reverse polarity" light connects from neutral to ground. Normally, the green light is on. If the polarity is reversed (at the dock pedestal or in your shorepower cord), there is 120 volts between what is supposed to be the neutral and ground and the red light lights.

Thinking about what I just explained, the green or "OK" lamp is conducting from the hot conductor to ground, not neutral and that is a "ground fault".

Temporarily disconnect the reverse polarity lights and see if the problem goes away.

Why would some boats trip a GFCI breaker and not others? Some boats may not have reverse polarity indicator lights or they may have burned out at some point and were never replaced. Or, they draw a small enough current that they don't trip the GFCI breaker.

If a boat doesn't have reverse polarity lights, they have burned out, or in your case, if you have to leave them disconnected because the marina won't replace the breaker, you can go to the electrical department of any home center and buy a plug in tester for about $10.00 that will test the incoming electrical power for reverse polarity and missing ground. Many also are able to test GFCI breakers and receptacles.

059ad950-bce7-4669-b398-90d2ea92b077_300.jpg
 
GFCIs are very problematic around water. As others have stated, there may be no real ground fault. Try getting a new GFCI installed. Or cleaning and drying the old one and it's connections and spraying it down with a good anti-corrosion spray like Corrosion Block or Boeshield.
 
quote:
Originally posted by Capt. Bill1

GFCIs are very problematic around water. As others have stated, there may be no real ground fault. Try getting a new GFCI installed. Or cleaning and drying the old one and it's connections and spraying it down with a good anti-corrosion spray like Corrosion Block or Boeshield.
Click to expand...


1) The GFCI breaker was already replaced (posted in the original post) and the results were the same.

2) A GFCI breaker or receptacle is not something that can be "repaired" by spraying it with anything.

GFCI breakers and receptacles are intended to protect life around water (and other places). A tripping GFCI device indicates a problem that needs to be dealt with.
 
GFCI Breakers or receptacles are not required if the receptacle is changed to a 30 amp twist loc. The GFCI breaker or receptacle is the culprit.
 
quote:
Originally posted by rawidman

quote:
Originally posted by Capt. Bill1

GFCIs are very problematic around water. As others have stated, there may be no real ground fault. Try getting a new GFCI installed. Or cleaning and drying the old one and it's connections and spraying it down with a good anti-corrosion spray like Corrosion Block or Boeshield.
Click to expand...


1) The GFCI breaker was already replaced (posted in the original post) and the results were the same.

2) A GFCI breaker or receptacle is not something that can be "repaired" by spraying it with anything.

GFCI breakers and receptacles are intended to protect life around water (and other places). A tripping GFCI device indicates a problem that needs to be dealt with.

Click to expand...


I missed the part that it had been replaced.

I wasn't claiming you could repair it by spraying it with anything. Only that in the past I've found that by keeping them clean and dry while protecting them and their wiring from moisture with a anti-corrosion spray it has kept them from becoming overly sensitive and tripping falsely.

Yes they are designed to protect life around water. But they are not happy getting wet themselves. I've lost track of how many of them I've replaced over the years because they were in a location that exposed them to to much moisture.

A tripping GFCI does not always indicate a true ground fault. Like any other device, a GFCI can fail.
 
Good discussion guys! We may get to the bottom of this yet! Can someone comment on the NEC standard related to the shore power receptacle. I'm referring to the one that my 30 amp shore power cord with twist lock plugs into on the pedastal. Is a 20 amp breaker acceptable, or must it be at least 30 amp? I'm referring to NEC 555.19(A)(4).
Does the NEC allow the use of GFCI breakers on the shore power pedastal, either 20 amp or 30 amp?
 
Seems to me the GFCI in question is doing what it's designed to do.

But all this talk about how to defeat the critter reminds me of the old practice of putting pennies in the fuse holder.

I've had a GFCI breaker on my shore power receptacle for a few years now. It has tripped ONCE, during a storm. The boat does not trip it.
 
quote:
Originally posted by stmbtwle

Seems to me the GFCI in question is doing what it's designed to do.

But all this talk about how to defeat the critter reminds me of the old practice of putting pennies in the fuse holder.

I've had a GFCI breaker on my shore power receptacle for a few years now. It has tripped ONCE, during a storm. The boat does not trip it.

Click to expand...


We can consider the shore power pedastal as feeding a building, not an individual circuit. One would not have a GFCI breaker feeding a building, there would be GFCI breakers on the individual circuits within the building as required.

In this case, the boat is the "building".

stmbtwle, I discussed why one boat might trip a GFCI breaker while another might not. In this case, it is tripping the breaker and the OP cannot have electrical power on his boat. His boat is equipped with GFCI breakers on the necessary branch circuits.

PatSea, I used to have an NEC code book but that was many, many years ago. You might be able to find one in your library, you might find the relevant section on the Internet. I would first ask the marina to replace the breaker with a standard breaker and if they refuse, ask them why. Explain to them what you've learned here and that without electricity available to your boat, you will have to move to another marina. If that doesn't work, bring in a certified marine electrician to check your boat for faults, then have a talk with the marina manager.
 
I'm not sure anybody is trying to defeat the GFCI.

As the OP pointed out:

"I read several places that it is difficult for even a properly wired boat with multiple circuits to not exceed the 5ma ground fault leakage that is the trip point for these breakers. To prevent nuisance trips but still provide adequate protection new boats are required to have an ELCI (Equipment leakage circuit interrupter) which protects the entire boat but is set to trip at 30 ma."

So while the GFCI maybe doing what it is designed to do, in this case it may be doing it for the wrong reason. I think that is all some of us are trying to point out.

But in the mean time he should do what is necessary to proof his system to make sure there is no real ground fault occurring. Unfortunately, that is not always easy. :-)
 
Just to clarify, I am not trying to defeat the GFCI. After all, it is my wife, kids and grandkids in addition to our dock neighbors in the marina who are recreating around my boat. I don't want anyone getting hurt. If my boat has an electrical issue I will fix it (and yes, finding the fault can be very difficult). I'm just not convinced at this point that my boat is the problem. There may be no problem at all other than a GFCI type breaker being used in an application it was not meant to be used in.

Rawidman, your explaination of the dock power pedastal being the feed to a building (my boat)makes a lot of sense. My boat has about 10 circuits in it. Certain outlets like the head and galley are protected by GFCI outlets just like in a house.
 
Hi all,

I would trouble shoot this way, and at all times remember to shut off the breaker on the dock with each step.. We have already changed out the breaker, so I would than disconnect the shore cord from the boat. If the breaker stays on I would then check the boat with all breakers and the main breaker off. If as I have read the gfi trips at this point I would disconnect the wires from the panel in the boat, tape them up and try again. If it still trips, remove the wires from the shore power point of entry to the boat and try again. It sounds like there is a ground problem between the shore power inlet and the panel. It could be corrosion or a bad wire, but the gfi is doing it's job. Trouble shooting is a pain in the ass. Take your time and be careful.

As others have said the marina has the right to control the use of electric by the size of the breaker or it could be they found 20 amp gfi breakers and didn't look to see if there were 30 amp gfi breakers. Depending on the brand they may not make a 30.

I'll watch to see how these steps go or if I don't understand the problem.

Billy K.
 
BillyK, thanks for the procedure to check each step along the way. Very logical and helpful. I'll try this and other chcks this weekend.
 
quote:
Originally posted by PatSea

The previous marina I was at for about 12 years had a standard 30 amp breaker without integrated GFCI.

Click to expand...


And you never had any problems at your old marina, your reverse polarity lights never came on and nothing has changes electrically wise on the boat.
You just moved to a new marina with a GFCI breaker and the GFCI protector part of it started tripping, correct?
 
I never had any electrical problems at my old marina while there for 12 years.

I don't have a reverse polarity light. I do have a light on my boats' breaker panel marked "shore power". I have always assumed that this light just indicated that shore power was connected and turned on at the shore pedastal. It always shows red when the shore power is plugged in.

Yes, I made some electrical changes after moving to this new marina. I installed a new bilge pump, changed out two cabin light switches, and replaced my A/C unit. However, the shore power breaker was tripping before all this work was done. I was connected to a breaker without GFCI at the time.
 
Let's back up a minute you were tripping a non GFI breaker prior to this work? Did I read that correctly?
Bill
 
quote:
Originally posted by Billylll

Let's back up a minute you were tripping a non GFI breaker prior to this work? Did I read that correctly?
Bill

Click to expand...


That's what I read as well. I'm really confused now.
 
OK, now you've changed everything and you've wasted everybody's time and effort. It's impossible to give meaningful advice if you leave out part of the story.

You've made enough changes that nobody can tell you on a web forum what the problem is. You need a marine electrician.
 
You must log in or register to reply here.
Back
Top