Weird Nuisance Breaker Trips

[2Cents]

Originally Posted by NorthCoastJoe

Have you looked at the back of your shore power connector?

Yes, no burns or melted plastic. All insulation looks good visually. Put SmartConnectors on a few years ago just after new set of cables.

[Statistical]

Originally Posted by 2Cents

Yes, no burns or melted plastic. All insulation looks good visually. Put SmartConnectors on a few years ago just after new set of cables.

Any chance you could have cross wired neutral and ground either on the cable on on the smartplug inlet?

As someone else suggested I would start from the pedestal inward.

[sinnerman]

It could also be a defective breaker.

I had an issue with an ECLI (leakage breaker at the box) in a new office I was building out. The breaker would trip randomly for no reason.

The electrician explained that the breakers get flaky with age, especially if the capacitors which are part of the leakage measuring circuitry inside start to get weak, it makes them overly sensitive.

Changing the ECLI breaker cured the issue.

Maybe the marina could check this out for you...

Cheers

[justinfinity]

Some euro and other boats that are made in 220V markets continue to ship to 120V markets with breakers rated for 1/2 the amperage needed in the 120V versus 220V environment. On our boat, things worked pretty well, even for years. But eventually after a pattern of mysterious tripping of breakers, we ultimately replaced all of the mis-rated breakers (on the boat) and have never had a problem since, at any marina, home or away.

[sinnerman]

I am not sure if anyone else posted this, but it is a good explanation of AC leakage on a boat.

https://panbo.com/gfci-and-elci-brea...their-warning/

Interesting notes on Inverters:

""..The presence of the inverter immediately attracted my suspicion that it was causing the issues. Inverters and reverse Y-adapters are the most frequent causes of ELCI nuisance tripping. A look around the boat revealed there were no breakers to isolate the inverter, so to test this theory I disconnected the inverter from the back of the AC panel. With inverter removed the boat was able to draw power from the marina without issue. Reconnecting the inverter immediately tripped the ELCI..."

".. 31.6.7.1.3 – The inverter/charger output neutral shall be grounded at the inverter/charger only when the device is the AC power source..."

"...So this means the inverter has to create a tie between neutral and ground when power is coming out of the inverter and break that tie when it’s coming from shore power. That’s because your boat isn’t a sub-panel any longer as the inverter or generator is the primary source of power.

Many inverters do this using relays, including the one onboard this boat. When there’s shore power coming into the inverter the relays are energized and that causes them to break the tie between neutral and ground. But, before those relays could receive power and break the tie the shore power ELCI breaker in the pedestal was seeing a fault condition (because of the tie between neutral and ground on the boat) and tripping the breaker..."


Cheers...

[sinnerman]

Adding some verbiage to my previous post above, per the ref. article, there is a 110 vac "normally closed" relay located inside the inverter. The relay receives its power from Shore Power .

The relay's function is to physically connect the boat's 110 volt AC neutral and AC ground (green wire) together when the inverter is supplying 120vac to the boat.

Being a "normally closed" relay, this means when everything is OFF, the contacts are closed (fail safe position), and the two wires are connected together.

The contacts only "open" and break this connection when the relay is energized when Shore Power is connected. (the actual purpose of the relay...)

Unfortunately, since the Shore Power pedestal-mounted ELCI is electronic, and the relay in the inverter is mechanical, before the mechanical relay has a chance to actuate, the faster-responding pedestal mounted ELCI has already sensed an improper neutral-to-ground connection and "tripped".

To solve this, the electrician installed a double-pole breaker on the AC output of the inverter. This (double pole) breaker makes/breaks both the 120 vac "hot" and 120vac "neutral" connections from the inverter to the 120vac bus.

Therefore, with the breaker "open" , the closed relay is "isolated" from the 120 vac system and no ELCI trip will occur.

The breaker would normally remain open at all times. It would only be closed when Shore Power is disconnected and the inverter is actually supplying the boat's 120vac power.

Actually, IMHO this is a much better way to wire the system. There needs to be a physical isolation of the inverter from the 120 vac bus unless the inverter is actually supplying power. If the inverter had an internal short, it could take down the entire 120vac system without having a way to isolate it...


Long winded, I apologize.

If I said anything incorrect, here please feel free to comment.

Cheers.

[s/v Jedi]

Originally Posted by sinnerman

Adding some verbiage to my previous post above, per the ref. article, there is a 110 vac "normally closed" relay located inside the inverter. The relay receives its power from Shore Power .

The relay's function is to physically connect the boat's 110 volt AC neutral and AC ground (green wire) together when the inverter is supplying 120vac to the boat.

Being a "normally closed" relay, this means when everything is OFF, the contacts are closed (fail safe position), and the two wires are connected together.

The contacts only "open" and break this connection when the relay is energized when Shore Power is connected. (the actual purpose of the relay...)

Unfortunately, since the Shore Power pedestal-mounted ELCI is electronic, and the relay in the inverter is mechanical, before the mechanical relay has a chance to actuate, the faster-responding pedestal mounted ELCI has already sensed an improper neutral-to-ground connection and "tripped".

To solve this, the electrician installed a double-pole breaker on the AC output of the inverter. This (double pole) breaker makes/breaks both the 120 vac "hot" and 120vac "neutral" connections from the inverter to the 120vac bus.

Therefore, with the breaker "open" , the closed relay is "isolated" from the 120 vac system and no ELCI trip will occur.

The breaker would normally remain open at all times. It would only be closed when Shore Power is disconnected and the inverter is actually supplying the boat's 120vac power.

Actually, IMHO this is a much better way to wire the system. There needs to be a physical isolation of the inverter from the 120 vac bus unless the inverter is actually supplying power. If the inverter had an internal short, it could take down the entire 120vac system without having a way to isolate it...


Long winded, I apologize.

If I said anything incorrect, here please feel free to comment.

Cheers.

None of that trouble exists with an isolation transformer (hint…)

[sailingharry]

I skimmed through the responses, didn't see the one I was looking for. Sorry if this is a duplicate.

I suffered with this when I replaced my inverter and modified the wiring to the typical system where shore power goes through the inverter. (Under the original installation, the inverter was either connected as a charger, or as an inverter, but never both, with two interlocked breakers on the main panel. As a result, it was never connected to shore power while also feeding ships)

It turns out that on many boats, including mine, there is a single neutral bus . This causes problems with an inverter. I split my bus in two and solved the problem. The first neutral bus consists of nothing but the shore power wire and the lead to the inverter (but would also include any loads not served by the inverter). The second neutral bus is everything downstream of the inverter.

[seasilk]

I had a problem similar to this on my Hylas 46 a few years ago. After replacing my charger/inverter at considerable cost and effort, I discovered that the problem was in a GFCI socket in the stern head. Replaced that receptical and the grounding problem was resolved.

[larrymac]

On two different boats, I have experienced these gremlins . In both cases, a competent electrician came aboard and assured me the problem was NOT the hot water heater element. In both cases, in desperation, I finally removed the hot water heater connections, and everything magically started working as expected! Of course, replacing the element fixed the problem. One boat was bonded, one was not. Since, on two more boats, I have simply replaced the heater element at the first sign of gremlins! I know, it’s wired, but so are gremlins!

[Bowdrie]

Originally Posted by larrymac

I finally removed the hot water heater connections, and everything magically started working as expected! Of course, replacing the element fixed the problem. One boat was bonded, one was not.

Not unusual, water heater elements are high on the list of devices that seemingly have a high propensity to leak electrons.
When chasing down electrical issues disconnecting all the wiring to the heater, (not just turning it off,) is a good first step.

[s/v Jedi]

Originally Posted by Bowdrie

Not unusual, water heater elements are high on the list of devices that seemingly have a high propensity to leak electrons.
When chasing down electrical issues disconnecting all the wiring to the heater, (not just turning it off,) is a good first step.

I use an outlet to plug the water heater into

[2Cents]

Originally Posted by sinnerman

It could also be a defective breaker.

I had an issue with an ECLI (leakage breaker at the box) in a new office I was building out. The breaker would trip randomly for no reason.

The electrician explained that the breakers get flaky with age, especially if the capacitors which are part of the leakage measuring circuitry inside start to get weak, it makes them overly sensitive.

Changing the ECLI breaker cured the issue.

Maybe the marina could check this out for you...

Cheers

Being they are all pretty new to us around here anyway, I would say it's not the ECLI. I had a bad one in my house as well once. Thanks though, appreciate any help and ideas

[2Cents]

Originally Posted by larrymac

On two different boats, I have experienced these gremlins . In both cases, a competent electrician came aboard and assured me the problem was NOT the hot water heater element. In both cases, in desperation, I finally removed the hot water heater connections, and everything magically started working as expected! Of course, replacing the element fixed the problem. One boat was bonded, one was not. Since, on two more boats, I have simply replaced the heater element at the first sign of gremlins! I know, it’s wired, but so are gremlins!

I have thought about this as well, but I have two, two pole shore power breakers, and separate breakers for each water heater. We are tripping the pedestal right when the shore power breakers on boat are closed, no power to any other load. Was this the case with your water heaters as well, breakers to them open, but tripping the GFI?

[2Cents]

Originally Posted by s/v Jedi

None of that trouble exists with an isolation transformer (hint…)

I don't disagree, but I am a right way all the time kinda guy, so part of me says it's been this way for 15 years, so the new shore equipment is just too sensitive lets put in two shiny new isolation transformers, problems solved.

The other part tells me there are numerous boats of similar age around us, that don't have this issue, so somewhere there is a problem that needs diagnosing, not hiding.

The idea of completely isolating boat from shore power using a transformer sounds like a phenomenally smart thing to do in general though.