GFI on. New shore power pedestals.

C

cjflip

New Member
Mar 3, 2010
2
Ohio, Lake Erie
Boat Info
1988 390EC
Twin 454 Merc.
6KW Westerbek
Raytheon 5 M Radar
13" 2015 Garmen GPS Chart Plotter
Engines
Twin 454 Merc
Has anyone experienced a problem when plugging and older searay into a new shore power pedestal with 30 or 50 amp service with GFI circuits? Out marina has upgraded to the new style and to code. The problem I'm having is when I go to switch over to line 1 and 2 at my panel it blows the circuit at the pedestal. The boat will run without blowing the breaker while only running one cable and selection switch at the Line 1 only position. I have a 1988 39EC you help is appreciated.

Thanks.

Chris
A Little Rocky
 
Very common issue. The cause is there is an electrical current leak to either the water, through the boat's/marina's ground conductor, or the other AC line. A properly functioning AC electrical system has equal current flowing on the Hot wire and the Neutral wire. GFCI monitors the current on both the Hot and Neutral; if there is an imbalance (30 milliamp or greater) then the GFCI will trip. Some marina's have a central GFCI (not at each point of use) which are 100 milliamp or greater.
So, your boat is leaking current to the ground, water, or the other AC power line. Primary causes are 1-generator, 2-Refrigerator, 3-water heater, 4-battery charger/inverter, 5-water intrusion, and 6-swapped conductors (neutrals most common) between line 1 and line 2. Many of the older generator installations do not switch the neutrals and consequently the neutrals are combined all of the time on the boat which naturally will trip the GFCI.
 
Marinas are upgrading to new electrical standards all over the US. Many older boats and even some newer ones have enough small leakages that new pedestal breakers will trip. This does not mean that there is anything wrong with your boat except that it is out of date with new standards. Rewiring the offending circuits fixes the problem.
 
I had a 390EC with a 6.5 Onan MCCK generator. I was the second owner and bought the boat when it was 9 months old with 75 hours on the engines, so it was all original and the electrical system was un-molested. in 1995 our marina was destroyed by Hurricane Opal and the power pedestals were replaced by newer GFCI eequipped ones. I sold the 390EC in late 1997. We never had a circuit breaker trip in the 2+ years were were using the new GFCI pedestal. So I tend to agree with ttmott, this problem is most likely on your particular boat and not a product of it being an "older Sea Ray".
 
There is a story about this very problem in the May 2018 issue of Power and Motoryacht magazine. Beginning in 2014 states began requiring compliance with newly updated electrical standards for marinas. As system upgrades at facilities become more widespread, tripped breakers are becoming more common and frustrating for boaters. The article explains the problem and what to do about it. It's worth the read. Of course, in the case of this thread, there may be a problem with the boat. But that could be due to the faulty installation of an aftermarket feature, the improper wiring of an appliance or inverter, or a boat that was fully compliant with standards when it was built, but trips more modern breakers. In any event, it is worth getting to the root cause of the problem.
 
Last edited:
sbw1 said:
Marinas are upgrading to new electrical standards all over the US. Many older boats and even some newer ones have enough small leakages that new pedestal breakers will trip. This does not mean that there is anything wrong with your boat except that it is out of date with new standards. Rewiring the offending circuits fixes the problem.
Click to expand...
I would disagree in that if there is leakage there is something wrong. Since the advent of the NEC (National Electric Code) which became prevalent in the 1930's and adopted post world war II as a national standard, isolation of appliances to earth ground was mandated; and that isolation is well below a modern GFCI trip point. The formal adoption of the grounding features in appliances and industry (the third conductor) in the 1950's further reinforced the necessity of isolation and protection from a shock hazard. A breakdown in insulation or a faulty assembly/installation should be the only means for electrical current to leak to the appliance frame, housing, or a boat's bonding / grounding network. the boat's bonding and grounding system is a safety feature and any current flowing through them is a problem not to mention the corrosion issue created. There is one exception, the generator; When a boat is running on a single phase generator that generator must derive it's neutral or common consequently the neutral conductors are bonded to the ground on the generator's frame similar as your house's neutral being bonded to the service ground in the meter base. There is not a neutral provided to your house by the utility, it is derived through connection to the ground in the meter base. This is why in older generator installations that do not switch the common conductors between shore power and generator power the marina's GFCI's trip. All other systems on a boat that was/is constructed to ABYC standards should be fully compatible to GFCI installations. Now that's not to say that when the boat was manufactured that the installer swapped neutrals between line 1 and line 2 which if a combination of loads were used would trip a land based GFCI; but then that installation would not be compliant to ABYC and NEC. Or that's not to say someone didn't monkey with the electrical system without really understanding the unique requirements for a boat.
 
Older thread but very relevant for me.... I was at a marina last with an all-new dock & electrical. I was using my 30amp x 2 to 50amp 240v adapter, I would pop the breakers on the pedestal as soon as I flipped my breakers on my panel on board. The marina told me that I would need to purchase a voltage isolator for my boat and they are close to $2k in price + installation... As old marinas update and new marinas come in this will be a major problem for our boat. What are my options ?
 
The Bill Collector said:
Older thread but very relevant for me.... I was at a marina last with an all-new dock & electrical. I was using my 30amp x 2 to 50amp 240v adapter, I would pop the breakers on the pedestal as soon as I flipped my breakers on my panel on board. The marina told me that I would need to purchase a voltage isolator for my boat and they are close to $2k in price + installation... As old marinas update and new marinas come in this will be a major problem for our boat. What are my options ?
Click to expand...
For one, don't use their electrician and watch what they're charging you for anything!
Seriously though, go back and read ttmott's responses. He pretty much spells it out.
 
HawkX66 said:
For one, don't use their electrician and watch what they're charging you for anything!
Seriously though, go back and read ttmott's responses. He pretty much spells it out.
Click to expand...

Thanks, I have read ttmott's post several times but for a non-electrician, it doesn't mean much to me...
 
The Bill Collector said:
Thanks, I have read ttmott's post several times but for a non-electrician, it doesn't mean much to me...
Click to expand...
Sorry. I know electronics & electrical work etc. My opinion is this is a relatively simple fix for a person that knows about a/c voltage. I doubt someone is going to give you an ah ha answer in layman's terms, but maybe. You'll probably want to grab some sort of an electrician.
 
The Bill Collector said:
Older thread but very relevant for me.... I was at a marina last with an all-new dock & electrical. I was using my 30amp x 2 to 50amp 240v adapter, I would pop the breakers on the pedestal as soon as I flipped my breakers on my panel on board. The marina told me that I would need to purchase a voltage isolator for my boat and they are close to $2k in price + installation... As old marinas update and new marinas come in this will be a major problem for our boat. What are my options ?
Click to expand...
Hey Mark - somewhere you have a leak to ground or leak to the other 30 amp supply neutral. Easy to find. You will need a good digital volt meter that can measure resistance. Turn all of the circuit breakers in the 120/240 panel to the off position. Measure each of the circuit breaker load side leads to the ground buss you should get infinity to close to that in resistance. If you find one or more that has low resistance then something in that circuit is leaking to ground and that will trip the marine GFCI. If all are clean and there is very high resistance then look to see if the neutral busses have crossed wiring; that is a neutral from one 30 amp power source is tied to the other side and thus the return for a single 30 amp supply isn't equal. The next thing is to look into the generator's transfer switch and make sure the neutrals are not tied to ground when the transfer switch is in the shore power position. Last but the most common culprit is the installation of an inverter. The inverter installation must switch the neutrals as well as the hot legs and multiple shore power conductors cannot be combined.
You can install an isolation transformer but in the end you have a leak to ground or a crossover in the neutrals or in the case of an inverter the neutrals are not switched. The marina's system is telling you that there is a problem in the boat.
 
To @ttmott 's point, I had to replace my main breaker switch between the generator and shore power due to the exact issue he speaks of. I ended up replacing the entire panel and made sure it was rewired to ABYC standards. To Tom's point I needed to have the neutrals (white wire) switched on/off by the breaker. As mentioned the generator has it's neutral wire tied to the frame and consequently the boats bonding system. That isn't wrong and how most older boats are wired but causes the need to have the neutral to be switched. The triple breaker at the panel just lifts the or switches the neutral because the when on shore power you cannot have the neutral (white wire) and the bonding (green wire) tied together as that what causes the breaker to trip. Now of course if you added or already have an isolation transformer installed none of that matters as the transformer handles the neutral/ground issues.

This is the panel that I added to my new AC distribution panel.
https://www.hodgesmarine.com/pan997...9S6TOI0wIaBqn9rXDZdEV72DzHPQQAWhoCjw8QAvD_BwE

When I added this I had to remove the rotary switch that switched between shore and generator power, although I think that may have been the issue from the start and was wired wrong by the previous owner. The rotary switches when wired correctly do switch the neutrals.
 
The Bill Collector said:
Thank you ttmott, the inverter is the only thing that is not OEM that I'm aware of.... Xantrex 3000 mine is older 2010 https://www.xantrex.com/power-products/inverter-chargers/freedom-sw-3000.aspx
Click to expand...

You should treat the inverter the same as the Generator and wire it as such, meaning a shore/generator switch on the main panel and a separate switch for the generator or inverter that runs through the main switch. That way the you are disconnected correctly from the shore power and grounded properly for the generator/inverter. Just make sure the neutrals are lifted/switched between the boat and the shore power with something like I mentioned in the other post.
 
You must log in or register to reply here.

Forum statistics

Threads
113,119
Messages
1,426,564
Members
61,035
Latest member
Lukerney
Back
Top