Boat Docks

[steve66]

The 2020 NEC requires ground fault protection (GFP) for feeders and branch circuits that supply piers and boat docks.

Sanity check: If a feeder with GFP supplies a panel on a pier, then the branch circuits from the same panel are also protected by the feeder GFP, correct?

Just verifying the code doesn't require a second level of GFP on each branch circuit.

I don't have any "shore power" receptacles, so the monitoring requirement for individual receptacles doesn't apply.

Thanks

 

[kwired]

Not too familiar with wiring in these areas, but I think so. Guess it comes down to if you need different trip level for branch circuits/feeders from that point on, or even class A GFCI protection.

 

[augie47]

If I recall correctly for the '17 Code there is a T.I.A. allowing the feeder protection not to exceed 100ma and the individual shore power branch circuits to be 30ma otherwise there is a lot of nuisance tripping.

 

[steve66]

If I recall correctly for the '17 Code there is a T.I.A. allowing the feeder protection not to exceed 100ma and the individual shore power branch circuits to be 30ma otherwise there is a lot of nuisance tripping.

Yes, but that's gone in the 2020 code, and only the 100 mA requirement remains along with GFCI protection for the receptacles themselves.

I know the feeder GFP will also protect the branch circuit conductors. But the code says "feeder and branch circuit conductors...shall be provided with GFPE.."

I can't figure out what their intent was? Seems to me the code is getting really sloppy with their language and completely failing to make the intent clear.

 

[don_resqcapt19]

The language in 555.35(A)(3) permits the feeder GFP to protect the branch circuits, however the language in (A)(1) requires individual 30mA protection for each shore power receptacle.

 

[steve66]

The language in 555.35(A)(3) permits the feeder GFP to protect the branch circuits, however the language in (A)(1) requires individual 30mA protection for each shore power receptacle.

That's what I thought about the feeder protecting the branch circuits. Thanks Don.

And I was mistaken earlier about the 30mA requirement being gone - as you mentioned, its still there for shore power receptacles. But I don't have any of those on this project, so it doesn't apply.