I have a 1984 ODay 28. My GFCI is next to panel of circuits in the galley directly below the companionway entrance from the cockPit. It is a 15 AMP unit in front of breaker type circuits of 30 AMP. We have Leaks at times in to the boat in that area. I think that is what has caused the GFCI to trip and ultimately fail occasionally. I’ve had the boat about 8 years and replaced the GFCI twice and it recently died for the 3rd time. My boat mechanic just bypassed it and recommends not putting oen back or just put in a non-GFCI normal dual outlet in its place. He says it is needless redundant and tripping before the acceptable load on the breaker would have tripped. Appreciate your thoughts
GFCI Needed?
- Thread starter Ran-Dee9229
- Start date
He's dangerously wrong. GFCIs are a lifesaving item. Breakers protect equipment. Which one is your priority?
It’s not redundant, like the others have said.
It also might not be undersized - you have 30A into the boat, but you might only have 15A for the outlets and 15A for the water heater. At least that’s how I remember our 85 28 being wired. The GFCI should protect the 15A house circuit at least.
It also might not be undersized - you have 30A into the boat, but you might only have 15A for the outlets and 15A for the water heater. At least that’s how I remember our 85 28 being wired. The GFCI should protect the 15A house circuit at least.
My recommendation is to get another boat mechanic - this one could kill you.
A quick review, what is a GFCI?? A breaker protects wires from excessive currents and sized in big numbers amps or so. If you look at your power cord there are three wires called HOT, Neutral and Ground. Normally current flows between HOT and Neutral, too much current and the breaker trips. No current should be flowing in the Ground or Protective Earth wire.
A GFCI measures the difference in the current in the HOT and Neutral wire, if that difference is too large then it trips. The reason for that difference could be current flowing through a human. Somehow you have managed to come in contact with the HOT conductor while the rest of you is touching Ground, So current is flowing through you from HOT to Ground and not returning via the Neutral. The trip current of GFCI is much lower than a fuse.
So a breaker and GFCI seem similar, both trip and turn off the electricity, but they are reacting to different problems. One is not the same as the other.
A GFCI measures the difference in the current in the HOT and Neutral wire, if that difference is too large then it trips. The reason for that difference could be current flowing through a human. Somehow you have managed to come in contact with the HOT conductor while the rest of you is touching Ground, So current is flowing through you from HOT to Ground and not returning via the Neutral. The trip current of GFCI is much lower than a fuse.
So a breaker and GFCI seem similar, both trip and turn off the electricity, but they are reacting to different problems. One is not the same as the other.
Also, is the GFCI mounted on the side panel, where the arrow points, the same as on the 85 model?
If so, the only place water could be leaking from is the bridge deck mounted traveler. If so, you should probably fix that, rather than just fixing the symptom of the failing GFCI. Leaks there will just lead to rotting core and rotting bulkhead in that area.
If so, the only place water could be leaking from is the bridge deck mounted traveler. If so, you should probably fix that, rather than just fixing the symptom of the failing GFCI. Leaks there will just lead to rotting core and rotting bulkhead in that area.
The GFCI is a necessary item in a damp environment. Your mechanic is correct in saying you're getting nuisance trips, but he is absolutely incorrect in saying it is not necessary.
The best solution is to move the outlet to a drier location. The GFCI should be the first outlet on the circuit. This will take some rewiring.
The best solution is to move the outlet to a drier location. The GFCI should be the first outlet on the circuit. This will take some rewiring.
I go back to a time when boats did not have GFCI receptacles and never had a problem. Perhaps it is quite difficult to establish a ground standing on the wood sole of a fiberglass boat's cabin. As I understand them GFCI breakers protect you against stray electrical current emanating from a faulty appliance. The appliance casing must be made of a conductor material and you must establish a good Ground to be shocked. I don't have any appliances that fit that category other than perhaps the battery charger of which I'm very careful when handling. Our boat has them and I have no problems with nuisance tripping so they get to stay, but I'm not very hyped about them. For the home they are a necessity.
GFCI protect against current leakage from the hot to the ground (green in boats, bare copper in houses). They will trip at very small currents, something like 5 milliamps. This leakage can come from any number of sources. I've had them trip because I was sloppy with a paint brush and barely touching an outlet. The stove top in our kitchen is on a GFCI and sometimes moisture from cleaning the stove top will cause the GCFI to trip because current leaks from the ignitor to ground.
This is very different from ordinary breakers and fuses which will trip because of a direct short between the hot and neutral wires or a direct short from hot to ground.
When an AC circuit is working properly the current flowing through the hot wire and the neutral wire should be equal and there should be no current flowing through the ground wire. Situations can occur when more current is flowing through the hot wire than the neutral. When this happens some of the current is going through ground wire which will energize everything on the ground wire circuit. That's dangerous, any device with a case ground will be energized. If a person touches the energized case and completes a circuit, they'll be shocked. On a boat that means the DC circuit can become energized with AC current through the common ground at the engine. Which again produces hazards and can leak into the water. Because the GFCI trips at a low level, it prevents this bad stuff from happening.
This is very different from ordinary breakers and fuses which will trip because of a direct short between the hot and neutral wires or a direct short from hot to ground.
When an AC circuit is working properly the current flowing through the hot wire and the neutral wire should be equal and there should be no current flowing through the ground wire. Situations can occur when more current is flowing through the hot wire than the neutral. When this happens some of the current is going through ground wire which will energize everything on the ground wire circuit. That's dangerous, any device with a case ground will be energized. If a person touches the energized case and completes a circuit, they'll be shocked. On a boat that means the DC circuit can become energized with AC current through the common ground at the engine. Which again produces hazards and can leak into the water. Because the GFCI trips at a low level, it prevents this bad stuff from happening.
An a/c circuit does not need a ground to operate. The current's return path is the neutral wire. Electrical code dictates that a circuit should have a ground wire leading to the ground wire at the power source in case there is a short circuit in an appliance and its case or metal components become energized. In such a case the ground wire would provide a more efficient path to ground than a person coming into contact with the faulty appliance. In a circuit with a ground wire properly connected and working the GFCI is just a redundant fixture. It is still a receptacle with a ground that in addition has a fast power disconnect switch. I just don't think that in a boat a person could that easily become a conduit to ground or let's say as easily as a person could in a home sitting in solid earth. I once tried installing a GFCI receptacle in a older boat and abandoned the project as the box was not deep enough to accommodate the fixture. Decided the existing grounding system was more than adequate given the environment. Don't clearly see how the 12V system could be energized by the ground wire of the ac circuit. The ground wire goes to the shorepower connector and not to the engine ground as the 12V does.
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The statement "you must establish a good Ground to be shocked" is not true.
Way back in the 1960/70's when the standards for Ground Fault Interrupters (Earth Leakage protection in the non US world) was being established, 20 mA was chosen as the tripping point for the current difference between live and neutral. This was based on the expectation that for most of the human population under most circumstances, that current would not cause enough loss of control that the shockee would be unable to disengage from the circuit. There are no absolute guarantees, just the statistical probability that at that limit more than 95% (if I remember right) of shocks won't be lethal. Since then much more sensitive GFI's have become available.
Now at 120 volts 20 mA will flow with a resistance of 6000 ohms, nowhere near a good ground and easy to achieve through wet skin.
Installing GFCI's require equipment to be in good condition. Poor insulation or connections between neutral and ground will trip GFCI's. Surges from lightening strikes can also cause trips. These nuisance events and the trouble of dealing with marginal equipment frustrate the ignorant into recommending against GFCI's, but you all should believe that if they tripping "for no good reason" you need them more than ever because possibly something seriously dangerous is wrong.
Way back in the 1960/70's when the standards for Ground Fault Interrupters (Earth Leakage protection in the non US world) was being established, 20 mA was chosen as the tripping point for the current difference between live and neutral. This was based on the expectation that for most of the human population under most circumstances, that current would not cause enough loss of control that the shockee would be unable to disengage from the circuit. There are no absolute guarantees, just the statistical probability that at that limit more than 95% (if I remember right) of shocks won't be lethal. Since then much more sensitive GFI's have become available.
Now at 120 volts 20 mA will flow with a resistance of 6000 ohms, nowhere near a good ground and easy to achieve through wet skin.
Installing GFCI's require equipment to be in good condition. Poor insulation or connections between neutral and ground will trip GFCI's. Surges from lightening strikes can also cause trips. These nuisance events and the trouble of dealing with marginal equipment frustrate the ignorant into recommending against GFCI's, but you all should believe that if they tripping "for no good reason" you need them more than ever because possibly something seriously dangerous is wrong.
Most of this post is simply incorrect and dangerous information.
It takes as little as 30 milliamps of 120 v AC to kill someone. The typical household and marine GFCIs trip at 5 milliamps, well below the level that will kill someone.
ABYC compliant wiring has both the DC negative and the AC ground connected at a common point. This is to ensure a path to ground for any current that leaks into the DC circuit. Connecting the AC Ground and DC negative also provides a pathway for AC to enter the water, which in freshwater can cause electroshock drowning. A GFCI prevents any residual current resulting from a ground fault from reaching the water because it trips. Current ABYC standards require an ELCI, which functions in the same manner but at a higher trip level, to be installed in the AC system before any branch circuits.
Nuisance trips occur for one of three reasons:
Faulty GFCI
Installation in a wet environment
A fault in the circuit, either in an appliance or in the circuit wiring.
Given the location of the outlet in the OP's boat, the second reason, wet environment, is a likely culprit. If moving the outlet to a drier location doesn't cure the problem, then there is probably a fault somewhere in the wiring or appliance he is using.
GFCIs should be the first outlet in a circuit as they protect not only the outlet but all outlets downstream.
For more information on residual current devices, take a look at a reliable source like the Wikipedia entry.
Residual-current device - Wikipedia
en.wikipedia.org
I agree with your assessment in regards to post #13 as it is nonsense. A GFCI is a life safety protective device that is attached to a particular circuit that is designed to fail safe if it fails at all. GFCI stands for ground fault current interruption so if the device detects something wrong it turns the circuit off regardless of whether it really is wrong or if it just goes over the threshold that is wrong for whatever reason. Some GFCI devices are more prone to fail than others talk to a good electrical shop to find what they use. They do not operate by magic or resentment so personally I would rather push the button again than get zapped.
This thread reminds me of a news item on TV tonight about a Tee shirt that said, : "It's a mask or a casket. Your Choice"..