Wiring options for floating dock

[Fred B]

Customer is getting a Tesla boat and wanting a 50A charger for it at the water front. Problem is dock is a floating removable dock about 60 -75ft out onto lake. Docks removed every winter. Does charger disconnect point, if I mount charger on the floating dock, need to be above the normal high water elevation on a non tidal body of water, or do I look at "normal" flood level in determining minimum height? Happening a lot more often and at higher levels every year. He is looking at a unit like this: so I don't see a cord that would reach if shore mounted. What wireing options would I have for this installation?

 

[steven765]

Hold up! Tesla Boat!!!!??? when did that become a thing?

 

[acrwc10]

Customer is getting a Tesla boat and wanting a 50A charger for it at the water front. Problem is dock is a floating removable dock about 60 -75ft out onto lake. Docks removed every winter. Does charger disconnect point, if I mount charger on the floating dock, need to be above the normal high water elevation on a non tidal body of water, or do I look at "normal" flood level in determining minimum height? Happening a lot more often and at higher levels every year. He is looking at a unit like this: so I don't see a cord that would reach if shore mounted. What wireing options would I have for this installation?

View attachment 2556229

Now I have to go look up "Tesla Boats" instead of getting some sleep! This makes me think of a bunch of questions like voltage drop to the unit, because it is probably a cord connection, to be removable. are they using a 4 wire 50amp range plug? or is it some special Tesla unit, or a combination of both? we had a problem about 9 years ago with Tesla wanting an exterior 50 amp receptacle but their angled plug wouldn't allow the outside cover to close to a water tight position.

 

[acrwc10]

Total Buzz Kill, Tesla doesn't actually make a boat yet. Too bad, it would be easier to tow than their car, when the battery dies.

 

[Fred B]

Now I have to go look up "Tesla Boats" instead of getting some sleep! This makes me think of a bunch of questions like voltage drop to the unit, because it is probably a cord connection, to be removable. are they using a 4 wire 50amp range plug? or is it some special Tesla unit, or a combination of both? we had a problem about 9 years ago with Tesla wanting an exterior 50 amp receptacle but their angled plug wouldn't allow the outside cover to close to a water tight position.

The plug in being suggested is a NEMA SS2-50 like you use for a gen connection. My big issue I'm seeing is the distance off shore for the connections, do I install the pedestal on the end of floating docks? If I do what sort of cable to run to it given that it would need to be removable at end of season as well as flexible and exposed to the environment? Or do I have shore mount pedestal, then we're talking about a very long "extension cord" to get out to boat for pluging it in?
Either way I see a very real possibility of someone dropping the cord into the water trying to hookup for charging and 50A 240V charge to water and metal dock surface. Ouch.
Will a simple GFCI breaker have adequate trip responce for that distances of of at least 120ft from closest shore point?
The pedestal mfg doesn't indicate that a GFCI is present in pedestal, so assuming I have to install one separately. Even if it does have an internal GFCI, if it becomes a dock mount, the fact that it too needs to be a plug in from shore power that service line also needs GFCI, will there be a problem having 2 GFCI's in series?

Total Buzz Kill, Tesla doesn't actually make a boat yet. Too bad, it would be easier to tow than their car, when the battery dies.

There is being built an electric boat on the same premise of a Tesla car although not made by Tesla, supposedly on same style battery platform. But currently the customer is getting one of this type from this company, not quite Tesla but a lot of functionality and retrofitting options.

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[steven765]

The plug in being suggested is a NEMA SS2-50 like you use for a gen connection. My big issue I'm seeing is the distance off shore for the connections, do I install the pedestal on the end of floating docks? If I do what sort of cable to run to it given that it would need to be removable at end of season as well as flexible and exposed to the environment? Or do I have shore mount pedestal, then we're talking about a very long "extension cord" to get out to boat for pluging it in?
Either way I see a very real possibility of someone dropping the cord into the water trying to hookup for charging and 50A 240V charge to water and metal dock surface. Ouch.
Will a simple GFCI breaker have adequate trip responce for that distances of of at least 120ft from closest shore point?
The pedestal mfg doesn't indicate that a GFCI is present in pedestal, so assuming I have to install one separately. Even if it does have an internal GFCI, if it becomes a dock mount, the fact that it too needs to be a plug in from shore power that service line also needs GFCI, will there be a problem having 2 GFCI's in series?

Length isn't the issue for the GFCI it's the impedance back to it. Speed of an electron is approximately that of speed of light, problem is those floating dock sections. Are they bonded sufficiently enough to give you the low impedance path back to the outlet if it contacts the water /dock? Personally I wouldn't mount the pedestal to a dock like that as the wiring will get damaged every year installing and removing the dock, even still the bonding will become an issue every year. Running a cord out to it and securing a loop at it's tie up point is probably the only way. As to the height 555.2(1)the electrical plane shall be min 2ft above the highest normal water level.

 

[hillbilly1]

Thomas Edison had an electric fishing boat he used at his winter home in Florida. Guess he was ahead of the curve on electric vehicles! LOL!

 

[oldsparky52]

The key to what to do IMO is dependant on the dock construction and the transition to shore.

Does the dock come out in sections? Is there a raceway for electrical? I would think the dock manufacturer would make allowances for this. They probably want a water line down there also.

If you put a 5 ma rated protection at the source, I bet you are going to have kinds of tripping issues. IIRC, you can get by with 30ma protection on the feeder then you can have 5 ma protection at the pedestal. That pedestal should be able to be ordered with 5ma GFCI breaker for the 50-A receptacle.

How far is it from the shore to the power source?

My 1st thought is 30ma breaker at the house, a w/p disconnect on shore where the W cable gets wired in each year (depending on jurisdiction you may need to get this above flood level). W cable in the dock to the pedestal. Drive additional ground rods at the disconnect for ground referencing the grounding conductor.

ETA: Do they even make 30ma 120/240 50A breakers?

 

[steven765]

ETA: Do they even make 30ma 120/240 50A breakers?

leviton does don't know about others https://store.leviton.com/products/...r-120-240-vac-lb250-ep?variant=16247518101576

 

[Fred B]

The key to what to do IMO is dependant on the dock construction and the transition to shore.

Does the dock come out in sections? Is there a raceway for electrical? I would think the dock manufacturer would make allowances for this. They probably want a water line down there also.

If you put a 5 ma rated protection at the source, I bet you are going to have kinds of tripping issues. IIRC, you can get by with 30ma protection on the feeder then you can have 5 ma protection at the pedestal. That pedestal should be able to be ordered with 5ma GFCI breaker for the 50-A receptacle.

How far is it from the shore to the power source?

My 1st thought is 30ma breaker at the house, a w/p disconnect on shore where the W cable gets wired in each year (depending on jurisdiction you may need to get this above flood level). W cable in the dock to the pedestal. Drive additional ground rods at the disconnect for ground referencing the grounding conductor.

ETA: Do they even make 30ma 120/240 50A breakers?

Dock comes out in 10 ft sections
Not mfg with any raceway
No mention of potable water
No info from mfg about internal breakers or GFI
The shore line is about 120ft from main house breaker panel

Kicker is the dock comes out in the centerline of frontage, and HO doesn't want the pedestal in the center so shortest distance to pedestal from the source also adds about 40 ft on the cord if mounting pedestal on shoreline, making the cord over or close to 100ft.