GFCI / GFI breaker problem

[JACCO]

ok this is my first time posting. here is the problem i have a panel box on a dock feed by a 2 pole 60 amp GFI breaker. when a new small live well is plugged into a receptacle which is feed from the dock panel the GFI breaker trips. but when the same live well is plugged into an outside GFI receptacle on the house the GFI receptacle holds. I should also say that the live well is on a 50 ' extension cord. i should also mention that other tools such as a heat gun was plugged into the dock receptacle it did not trip the GFI breaker. i know that is alot to take in really wondering what is going on . also the GFI on the house is working properly.

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[GoldDigger]

It is possible that the live well has a leakage to ground which is right in the 5ma area and therefore can either trip or not trip a normal GFCI breaker or receptacle unit depending on where those two things are within the manufacturing tolerance curve.

It is less likely be still possible that something about the environment (resting on conductive surface, etc.) is which the live well is placed could account for a difference in the leakage current.
And finally, if the 60 foot cord has capacitive or fault leakage in the low milliamp range that might make the difference of whether the total leakage in the protected circuit, including the live well, is above or below the GFI/GFCI threshold.

 

[don_resqcapt19]

How far away from the panel is the 60 amp GFCI? What other loads are connected when the GFCI trips? It could just be the the cumulative leakage current on the feeder conductors, assuming that the 60 amp breaker is remote from the panel, and the other loads is close to the trip point and the leakage from the live well is enough to cause the trip.

 

[Haji]

if the 60 foot cord has capacitive or fault leakage in the low milliamp range that might make the difference of whether the total leakage in the protected circuit, including the live well, is above or below the GFI/GFCI threshold.

Whether the 60 foot cord is the sole issue may be checked by disconnecting the live well and energizing the cord only through the GFCI.

 

[JACCO]

gfi breaker / gfi problem

gfi breaker / gfi problem

the cord was mentioned because that is how the live well is powered temporarily from the gfi at the house. the live well is next to the dock panel where the outlet is that seems to trip the gfi breaker every time. I believe the live well has some leakage to ground.going to bring 20 amp circuit to dock and install same kind of gfi that is at the house. thank you for your input. this is my first time on this site and i will be using it a lot more. thank you!

 

[GoldDigger]

The way to know for sure is to carefully and safely measure the current in the ground lead of the cord attached to the well.
It is also possible that there is no ground at the house receptacle you are testing on.

 

[Strombea]

I have always been under the impression that a 120 v circuit off of a 240v GFCI breaker would not work because the phases are unbalanced thus tripping the 2 pole GFCI breaker. A 60a 240v breaker for like a jacuzzi? That wouldn't maesure leakage to neutral it would measure between phases. You need a single pole GFCI breaker for it to work. Or a GFCI plug on a 60 amp non GFCI double pole. But obviously sub down to 20amp OCD for standard plug.

Im assuming it's double pole GFCI breaker cuz 60 is pretty high for it not to be.

 

[ActionDave]

I have always been under the impression that a 120 v circuit off of a 240v GFCI breaker would not work because the phases are unbalanced thus tripping the 2 pole GFCI breaker.......

Not true. A two pole GFCI breaker can handle 120V loads no problem.

 

[kwired]

Not true. A two pole GFCI breaker can handle 120V loads no problem.

There are two pole GFCI breakers with no neutral connection - those would not work if a 120 volt load is supplied.

Square D catalog shows 50 amp and below GFCI breakers with 120/240 ability, but the 60 amp GFCI breaker they show is two wire 240 volt only. If OP has this or other similar breaker then that is a problem.