Pedestal trips on plug in.

[Grahambda]

After spending 6 months doing major projects and upgrades including victon electronic upgrades at one Marina, we finally set off today heading down south in Florida. Only to find the first Marina we come to, with the newer pedestals, trips timmediately on the 50 amp and even the 110. I understand these new pedestals adhere to a more recent safety code and trip more easily. But doesn't disguise the fact we clearly have a problem, the issue is how do we find out what's causing the tripping? I have the original electrician that did the work on the boat this afternoon looking at the issue but he's running out of ideas. We've tried turning everything off, all the switches but it even trips with the panel completely off. So there's no way in identifying what is causing the issue by going through a process of elimination breaker by breaker. Any suggestions as to how we find out what the issue is would be greatly appreciated.Thanks (btw have tried different power cords and pedestals,still trips)

 

[Comodave]

Our last boat did that. It had 2 30 amp inlets. The problem was that the neutrals were on one bus. I had to figure out which neutral went with SP1 and which went with SP2. Added a 2nd neutral bus bar and it works fine.

 

[TowLou]

Is your neutral bonded to ground before the main or in the main? Should not be.

Otherwise inspect the run from main to plug.

Any issues on older pedestals?

 

[sunchaser]

In addition to turning off all the switches, did you turn off your inverter? Seven years ago when the new pedestals started coming on line we rewired all our 110 volt grounds so that they all came to one bus bar. Then one and only one line from the bar to the ship's ground.

We still turn everything off including the inverter prior to plugging in.

 

[boatnbump]

Start with the power cord only not connected to the boat. I had a cord that had saltwater in the plug that was tripping it.

 

[Insequent]

My electrician resolved a tripping problem similar to that a year or so ago. Tripping most, but not all of the time on connection.

I have a Charles isolation transformer, another Charles unit as a step-up (or step down) transformer, and a Victron Quattro inverter/charger. The second Charles enabled me to use USA 120V/60Hz pedestals before returning to Australia with 240V/50Hz.

The issue was explained to me along the lines of those three transformers having a lot of iron to align in a magnetic field on initial power-up. This creates surge, a very, very short surge to be sure, but long enough to trip modern pedestals. He did a couple of things to "slow down" or manage that initial surge. He added both a capacitor and a varistor. Works perfectly now, not one trip on initial pedestal connection since. I guess its analogous to the "soft start" components some people need to add to their A/C units.

 

[SteveK]

Eliminate the inverter as a source. The neutral and ground may be closed on inverter.
Another thought is having a neutral and hot wires reversed.

 

[DrissZougari]

A reversed line and neutral is your most likely culprit.
Hint, if the boat works fine on the Generator (shore cord disconnected from the dock), then you have a reversed L&N in one of these locations.
- The shore power cable.
- The bulkhead Connector (s).
- The termination at main switch on the panel.

 

[Grahambda]

Thanks everyone for the suggestions, I have forwarded to the electrician, hopefully one will be the fix.

 

[fgarriso]

Is your electrician a ABYC certified marine electrician?

If not find one who is!

 

[Grahambda]

Eliminate the invertor

Eliminate the inverter as a source. The neutral and ground may be closed on inverter.
Another thought is having a neutral and hot wires reversed.

Thanks, yes electrician is back on board this morning and he plans to disconnect the new Victron multiplus inverter charger to see if that is the cause.

Everything works fine when running on the generator by the way.

 

[twistedtree]

There should be a breaker on the boat, probably near where the shore power inlet is located, that is the first breaker before shore power goes to anything. Does the shore breaker trip with that breaker turned off?


Do you have a galvanic isolator, or an isolation transformer?


At the boat's shore power inlet, but a meter between neutral and ground. Is there any connectivity? Check with the continuity beeper, but then also measure the resistance.


And are we talking about 30A 120V service, or something else? You said is fails on 50A as well as 110. I don't understand what you mean by that.

 

[Grahambda]

Problem fixed !

Here is the electrician explanation, related to a Victron Mulitplus invertor charger..

I took the neutral coming in the boat off the buss bar, routed that through the inverter AC in, then took the neutral out of the inverter and brought that to the neutral buss bar. So the flow of power had to go through the inverter first and then to the neutral common buss bar.

 

[rslifkin]

Here is the electrician explanation, related to a Victron Mulitplus invertor charger..

I took the neutral coming in the boat off the buss bar, routed that through the inverter AC in, then took the neutral out of the inverter and brought that to the neutral buss bar. So the flow of power had to go through the inverter first and then to the neutral common buss bar.

Neutrals shouldn't be shared on the inverter input and output. If you've got an isolation transformer, it'll probably work ok. But without one, that can cause a GFCI / ELCI trip when you plug the boat in with the inverter on, as the inverter ground relay won't release fast enough and the shore breaker will see the neutral / ground connection if there's any loads running that aren't run through the inverter.



The correct thing to do is to add an additional neutral bus for anything that's powered from the inverter. That way the inverter input and output neutrals remain separate.

 

[SteveK]

Here is the electrician explanation, related to a Victron Mulitplus invertor charger..

I took the neutral coming in the boat off the buss bar, routed that through the inverter AC in, then took the neutral out of the inverter and brought that to the neutral buss bar. So the flow of power had to go through the inverter first and then to the neutral common buss bar.

Shore breaker tripping solved.

Mentioned already that there is a need for separate neutral buss bars unless all systems can be powered by the inverter only. What was done suggests all loads run through inverter now, at least the neutral leg.

ETA: example. my inverter is fed hot and neutral line through a dual 30 amp breaker. So it can only feed a load up to 30 amps. On board can draw up to 90 amps so everything cannot be on at one time through inverter. The line out of inverter goes to a separate neutral buss bar for those items that the inverter can handle in total. The hot line out only feeds the circuits of this separate neutral buss bar.
All other loads are fed direct and not through the inverter.

 

[sunchaser]

Thanks, yes electrician is back on board this morning and he plans to disconnect the new Victron multiplus inverter charger to see if that is the cause.

Everything works fine when running on the generator by the way.

Something to think about for the future is an inverter bypass switch. This accomplishes two things. First if your inverter goes bad you still can use shore or genset power. Secondly when plugging into the newer GFIC setups you can ignore the not so “automatic” inverter/charger neutral switch with the bypass activated.

With vessels that are space challenged ITs are not easy to locate. Plus they can be noisy and generate heat. Thus neutral, grounds, thoughtful re-wiring and bypass switches come into play.

 

[Trawlerman]

I have fixed several boats on our dock that had this problem when the marina installed ELCI breakers. The issue was most commonly that the inverter installer did not separate the inverter neutrals from the non-inverter neutrals.

The second most common issue was that the shore-off-gen switch was wired in such a way that the generator neutral/ground commonality (required for gen use) was being "felt" due to this miswiring of the gen-off-shore switch. Some other issues that cropped up were:
1.) The boat had a galvanic isolator that "tested" the neutral ground separation, causing the ELCI to trip.
2.) The boat had an old-school reverse-polarity indicator that consisted of a relay with the coil connected between the neutral and ground.
3.) The boat had a stove with the old type of common heating coils, and there was leakage between the nichrome heater wire and the outer metal coil case due to leakage in the ceramic insulation inside the coil.
4.) The boat had a domestic type dryer installed and the neutral was grounded.
Lots of hair pulling involved in finding the specific issue.

 

[Comodave]

What year is your boat? It is very common in 1980 and 1990s boats to have the neutrals on one bus bar. As I posted above our last boat would trip the GFI breakers on the dock with everything turned off on the boat. As soon as you plugged the shore power cord in the breaker would go off. All the neutrals were on one bus bar. Separated the neutrals and added a second neutral bus bar and all was fine. If your electrician can’t figure it out then get a different electrician because this is a common problem, getting more and more common as marinas rewire and move to the new breakers on the docks.

 

[SteveK]

I have also found if you do have two separate neutral bus bars then the hot must also be on the source of hots where the neutral originates.
The ground is common connection point to shore.
The neutral/hot pairs must be connected to the same power source pair. Both to load of inverter or to load of shore power. Then there are the idiot lights on the panel that light up to show your breaker is on, they too must have the pair go to the same load pair.

 

[Comodave]

Absolutely the neutrals on the bus bar for SP1 need to match the hots for SP1. Same with SP2.