Boat dock

Location
Harrodsburg, KY
Occupation
Electrical Engineer
I have a marina that is having problem with a customer. GFCIs on the marina are melting and the customer says it is not his boat causing the problem. Without looking at it yet, I am presuming that he has an open neutral or ground somewhere on his boat and the problem is not with the marina. How would I approach this problem?
 

Little Bill

Moderator
Staff member
Location
Tennessee NEC:2017
Occupation
Electrician
Sounds more like a poor connection causing a high resistance, which causes heating and as a result, melting the GFCI. Could be corrosion due to being near the water. Only way to know is check both the GFCI and the customers equipment he is plugging in.
 

mikeames

Senior Member
Location
Germantown MD
Occupation
Teacher - Master Electrician - 2017 NEC
What exactly is melting the marina GFCI? If a customers boat has a loose connection it may cause the GFCI to trip but not melt. As bill said loose connections generate heat so if the GFCI is melting there is an issue there regardless of what's going on with the load (customers boat). If its tripping then its possible its on the boat.

Perhaps its a large boat putting a large load on the GFCI which has compromised connections so when fully loaded the problem presents itself. On a smaller load it may not. I would start at the melting GFCI. It should tripout from overload or a ground fault before it melts. It should never melt regardless of what its feeding. I would measure the current the boat is pulling on each leg and neutral to get an idea of the load. I would measure VD across the breaker by itself and under load. I would ask if everything electrical on the boat is working properly.

Then go from there.
 
Last edited:

synchro

Senior Member
Location
Chicago, IL
Occupation
EE
More than one GFCI has melted? Did a melted GFCI get replaced and the replacement melted? Or are there GFCI's on other outlets melting?
How does he know there are no bad connections in the plug he is using?

And the plug or entire shore cord should've been replaced if the receptacle melted when it was plugged in. If it wasn't replaced then it's not surprising that the problem persists.
 

mikeames

Senior Member
Location
Germantown MD
Occupation
Teacher - Master Electrician - 2017 NEC
What size are we talking about? I am envisioning a 50a breaker? Are we talking 20a 120v reseps?
 
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