4788 shore power problem-gctid805282

[stargazerwa]

I am on a municipal dock today with recently installed dock power that I suspect is more up to date then most. Each breaker has a test switch like a gfi.

Everytime I connected to shore power the breaker on shore would throw, I tried several posts. I finally isolated to to line 2 on the boat. With the parallel switch for line 2 off I can run lines 1 and 3 (3 paralled to 1) with out tripping the breaker just turning the parallel for 1-2 on will trip it even with all of the line 2 breakers off. All three lines work fine on the generator and worked fine on our home dock this morning.

Any ideas, I a wondering if we have a leak on line 2 that dock system is detecting. I am positive the breaker is not throwing for over current. It's always something

[smitty477]

I would start by throwing every single breaker on line 2 to 'off'..

Then with power to the boat 'off' parallel line 2 then power 'on' tp the boat.

If you get a trip then the problem is somewhere between the boat side connector and the parallel switch.

If you do not get a trip then cycle each line 2 breaker to 'on' one at a time until you do get a trip.

Track which breaker(s) cause a trip and work from there.

[Ruffryder]

Yellow test button is the GFCI breaker,

Purple button is combination of AFCI/ GFCI

[Destiny_4588]

If you have an inverter, turn it off and see if the issue goes away. ( If you do not check the gen set for the ground being tied to a neutral.)

If so then turn the inventer back on but not the breaker for AC input power (Charger side/transfer switch).

If that Dockside trips your issue is on the inverter ground and you need to separate all your AC grounds that the inventer uses from the dockside AC (generator) grounds. Inexpensive part for another bus bar, just takes a alot of time going from green wire to green wire with a meter and looking for continuity with your neutral bus or load bus as that is exactly what GFCI looks for)

If dockside does NOT trip then try to add the AC Charger side of the inventer by turning the break on ...if dockside trips issue is with Inverter Transfer switch (not a real fix other then call manufacture and see if that part is replaceable or upgrade-able). Some of the transfer switches combin neutral and ground)

Moved last year to a brand new marina with new AC dockside and spend a weekend figuring this out. Every boat that was around all said issue is on the inverter side and it was.

Ps. Also found the Genset had the ground was combined with the neutral which also caused an issue.

Happy hunting....this issue will effect all boaters over the next 5-10 years as every state is requiring these upgrades and our older boats were not wired for them.

[stargazerwa]

So with all of the line 2 breakers off the shore breaker will trip by just switching the parallel on, which doesn't make sense to me. The invertor is on line 3 and doesn't seem to trip it.

[MonteVista]

The genset or inverter GND-to-NEUTRAL connection should happen ONLY if the genset or the inverter is the active AC power source. When you flip the switch to use the genset or the inverter should be the only time when its gnd and neutral lines should be connected. Otherwise, those lines should still be connected BUT on the dockside. If your dockside panel has a sophisticated line tester so it detects the genset or inverter as selected, then it may be tripping the circuit breaker. Either set the genset/inverter selection switch to off or turn the dock panel off.

Good luck.

[Guest]

Electrical issues can ruin a boat. If you can't find it easily, hire a *good* marine electrician and let him fix it.

My go-to guy in Seattle is Matt Netting, owner of Petrel Marine, 206-327-0676. Not only is he super-knowledgeable with all the right credentials, he is also really nice and thorough. I'm guessing that one of your connections has a mis-connected shore ground to DC neutral. I could be wrong, which is why I hire an expert. :-)

Good luck!

Rob

[HotwireJim59]

I think your ground and neutral wire may be bonded more then once. Which then makes the ground a current conducting wire. That will set off a GFCI circuit protected device every time. So per your statement, it is not down stream. That is because all breakers were off. You have a two pole breaker for line two. That turns power on to all your separate loads. Try it again with that off. That way you can separate between the parallel switch. Or the main breaker for line two. In the marine world, both the Hot and neutral are disconnect by a breaker. Safety issue. Maybe a defective breaker? Or some how wires are crossed up at the P switch.

[HotwireJim59]

The service that feeds the transformer for the marina. There maybe a few of them depending on size of marine. Each transformer has a Neutral and ground bond point. It is usually in the service equipment. Doesn't matter if it is single phase or three. The Neutral and ground connects one time only. The chase of the service gear panel is also connect to neutral buss via a screw or jumper. When you disconnect from the shore power and connect to your generator. That becomes your service point. The neutral and ground must be bonded from the generator. The same way as shore power. When the generator is off the neutral and line conductor are isolated from ships power and there for shore power. If you do not have isolation. It will trip a GFCI protected circuit. If a second bond should happen down stream of the incoming service. The grounding conductor become a current conductor just like the neutral. That is why the bond happens once.

[stargazerwa]

Thank you everyone, I am not completely stupid about electricity but I am not quite sure how to process some of this information! Maybe getting an electrician is the best course of action.

1. When I parallel line 2 it will trip even with the master two line breaker off, that doesn't make sense to me, does it for anyone else?

2. It all works fine at my marina, every other marine and the genset except this new public dock in Gig Harbor whose wiring is less than a year old.

3. The inverter is powered by line 3 which I can parallel and doesn't trip the curcuit.

[MonteVista]

So, Line 2 breaker is off, on the boat the Parallel for line 1 and line 2 is on, and you trip the breaker at the dock?

If that is the case, I suspect that the dock panel may have the NEUTRAL and GND lines reversed on line 2. If so, line 2 current would complete through a load on the boat and make its return on what it thinks is the NEUTRAL wire but actually returns through the GND wire. At the dock panel, a GFC-like circuit breaker senses that line current is not returning through the neutral wire and trips. I am not 100% sure if the issue is at the dock or the boat. Here is what I would do.

Using a single dock panel outlet and a single plug/cable, one by one plug the cable to a shore outlet and, in turn, to the boat1, boat2, and boat3 sockets on the boat with their circuit breakers ON and any/all parallel switches turned to OFF. Try this with each of the dock panel's outlets. Either one of them should trip or the boat should give a reverse polarity indication. Otherwise, check if a reverse polarity is indicated when you throw the parallel switch.

Good luck.

[stargazerwa]

The mystery continues.

This morning I ran a second shorecord from another post to line 2, it shows voltage and a green polarity light. Turn on the two pole line breaker nothing happens, try adding a load nothing happens. Shows line 2 voltage but none of the line 2 breakers are energized and the breaker on the pole never blows.

With only line 1 connected, the shore breaker still blows when I parallel line 1-2

[MonteVista]

"stargazerwa" post=805418 wrote:
The mystery continues.

This morning I ran a second shorecord from another post to line 2, it shows voltage and a green polarity light. Turn on the two pole line breaker nothing happens, try adding a load nothing happens. Shows line 2 voltage but none of the line 2 breakers are energized and the breaker on the pole never blows.

With only line 1 connected, the shore breaker still blows when I parallel line 1-2

I think, this is indicating that reverse polarity or a short exists on your boat.

[mmichellich]

Look behind your power panel. Look closely for wires and connections that have fatigued and broken off the main line breakers, the doubke ones at the top of each column). I replaced every one of them, both gen set and shore power, all 6. Finally company changed the design. Leads to all kinds of weird situations and unsafe situations. Check every wire going to a breaker and make sure terminal has not broken off a breaker.

[MonteVista]

Try the following:

- Plug in Line1 at the dock, but don't plug in line 2. BE CAREFUL, LINE 2 plug at the cord will be live!. Now turn Parallel ON. Check if reverse polarity is indicated or circuit breaker trips.

- Repeat the same but plug in Line 2, leaving Line 1 unconnected. Check what happens.