50 amp shore power connector but 30 amp breaker at the panel - what do I need to change?

longy

Overlord of Anarchy
7,013
1,296
San Diego
Depends. Most marina's will supply 50 amp thru 2 hot legs of 30 amp apiece. So a pigtail that just does not connect to both hot legs does the job.
Alaris is planning to have one hot leg carrying 50 amp connected to boat. In this case an adapter will allow the cord to be plugged in, but the boat would have 50 amps delivered to main panel. Potentially bad - but this is why one needs an input breaker right at ship's input socket.
 

Alaris

Super Anarchist
1,871
691
Annapolis
Depends. Most marina's will supply 50 amp thru 2 hot legs of 30 amp apiece. So a pigtail that just does not connect to both hot legs does the job.
Alaris is planning to have one hot leg carrying 50 amp connected to boat. In this case an adapter will allow the cord to be plugged in, but the boat would have 50 amps delivered to main panel. Potentially bad - but this is why one needs an input breaker right at ship's input socket.
To be clear—I’m not changing that. The boat was wired with 50/125 from the factory. It’s a deprecated standard though.
 

mckenzie.keith

Aspiring Anarchist
861
290
Santa Cruz
Okay, this breaker box has a 50A 125V ELCI. Plenty for my needs. And it has two extra breaker slots. What’s not clear to me from the drawing is, can you wire this so the breakers are protected by the ELCI, since I don’t see a bus, or are they standalone?

Pardon my ignorance, I am going to talk to an electrician before I install anything, but I’d rather not start paying them until I’m pretty sure of what I want to do.

View attachment 558149
I guess you could put a breaker/switch in the unused positions and just jumper from load 1 or load 2 to the input side of the breaker/switch. Maybe they sell breakers that will work for that purpose.
 

mckenzie.keith

Aspiring Anarchist
861
290
Santa Cruz
What if one's 30A boat was relocated to a slip with 50A at the dock? Is it just a matter of a pigtail with the right ends?
This will work in practice. I am not sure if some kind of wiring enforcement police will throw you in jail. But you can buy pigtails like that at HW stores or Amazon (that adapt 120/240 50 Amp outlets so you can plug in 120/30 Amp cords.)
 

Leeroy Jenkins

Super Anarchist
1,702
691
Vancouver
This will work in practice. I am not sure if some kind of wiring enforcement police will throw you in jail. But you can buy pigtails like that at HW stores or Amazon (that adapt 120/240 50 Amp outlets so you can plug in 120/30 Amp cords.)
Thanks. I have a chance to move to a much better (for me) slip in the spring, but it may be set up with 50A
 

Slick470

Super Anarchist
2,056
323
Virginia
I would run the pump off the same breaker as the AC, but with a small inline fuse somewhere (preferably somewhere accessible).
I was curious and looked up a couple install manuals and it appears that on some of the A/C units you wire the pump to a connection block on the A/C unit controller, but if not that, then I agree, same breaker with an inline fuse would work.
 
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