Our marina replaced the entire...

[Sundance]

Our marina replaced the entire shore power electrical system, including super-sensitive breakers (5mA). We now have trouble with the breakers tripping frequently. There are 4 boats on a circuit and we've tried to isolate the problem to one boat, but each one has the same result. In The problem runs throughout the entire marina, and the management is reluctant to listen to our concerns. In the mean time, does anyone know of a marine electrician in northern Ohio that can check the onboard wiring of our boat for leakage? '88 Weekender with twin 5.7s and straight shafts. Thanks in advance for any help.

[lvanb]

Sundance, the 5mA GFP (ground fault protection) that your marina has installed on a shore power circuit supplying 4 boats is most likely too restrictive for a marina environment and the converters, battery chargers and inverters utilized on boats. The leakage current from 4 boats on the same shore power circuit will be additive and most likely significantly greater than 5mA. Here is a link to an excellent article on marina AC leakage current: https://www.marinadockage.com/technical-bulletin-understanding-ac-leakage-current/. Suggest that the marina remove the GFP at the circuit level and place at each shore power pedestal. Also suggest research into current NEC requirements for marina GFP protection. GFP at the circuit level may not be required (or recommended) as long as there is GFP at the shore power pedestal.

[PETERW]

Check the main circuit breakers on your boat if they are the type that trip at low voltage condition preventing damage to ac compressors etc. These have a third connection that provides a slight leakage path to ground that the shore gfi does not like.
I replaced mine with breakers that do not have that feature or you can just cut that connection..

[Airwaves]

@PETER PETERNOUSCHEKdo you know the name or type of circuit breakers that have a leakage path, or how do you describe the path? My marina is having same problem.

[PETERW]

The main 30 amp breakers that were on my 1993 Silverton 41 were identified as having an auxiliary coil. Once I replaced these with regular breakers the problem went away. Open your panel and look at the back of the breaker. If you you have 3 connections you have found the problem. Attached is a picture of one of my old breakers.

[SeaMax]

More than likely the problem is the size of wire the Marina used to supply the panel that's splits off to 4 boats. If the wire size is to small for the load, the voltage will drop and when voltage drops, amperage goes up - thus causing your breakers to trip. Maybe you could have the other 3 boats disconnect completely and see if your problem persists. Of if you have a good volt meter, check the voltage on your boat when all systems are running and the other boats are connected as well. This is all stuff that any good electrician will look at.

[lvanb]

SeaMax, GFP (ground fault protection) is not affected by load current levels. A marina operation is commercial and must abide by NEC requirements and installation by qualified electrical contractor. I am sure that the issue is not wire size.

[High_priority]

My boat Mecanic is going to install a in line galvanic isolator which is supposed to stop the back feed to the main breaker. 88 340 Express Cruiser Portland Oregon

[SeaMax]

Ivanb: I beg to differ - low voltage can cause a GFI to trip. Do your research. I'm just trying to help Sundance and posting incorrect information does not help him.

[Jeff_pearsons]

You can find what is causing it by turning off all your onboard breakers . Leaving one on at a time . If shore power trips it is a load on the breaker which is casing the leak to ground.

[lvanb]

SeaMax, not true. GFI/GFP operates on current only. Voltage is not monitored. I am an Electrical Power Engineer with 47 years experience - not incorrect information... I agree, posting incorrect information does not help anyone!

[lvanb]

High priority, galvanic isolation has nothing to do with GFI/GFP. May eliminate GFI/GFP on shore power circuit. Do not recommend this solution.

[High_priority]

Ok with All this back lash 47 years electrical experience What do you suggest for all the older boat owners to do regarding GFCI breakers. I had to monitor my boat during a freeze daily to make sure it had power. I’m looking for a solution.

[PETERW]

Good explanation of GFI function
https://www.westmarine.com/WestAdvisor/ELCI%20-GFCI-Electrical-Shock-Protection
Another explanation could be surface salt/dampness on Ac circuit wires close to connectors or exposed junction boxes. I had a personal slight shock experience touching insulated exposed ac circuit wiring years ago.