50a Y pigtail all summer

Liberty44140

We are moving slips this summer and my new slip has a 50a. My boat is two 30a like most boats 30 - 40 ft. All of the docks in our marina under 40' are two 30a outlets, my entire 40 slip pier is two 30a outlets - but they changed my slip to a 50a for the previous occupant's big newer pursuit. Marina doesnt want to change back to two 30a, they want me to use a Y adaptor. I am saying no as I've read that the 50 to 2 30a are for cruising, vacations, not all summer use. Fire hazard. Thoughts from the electrical experts here? 

Grahamu

The 50 amp pedestal outlet is probably 125V/250V and the "y" adaptor will split the feed into 2 legs of 125V from different sources. Never known it to be a problem except your overall amperage load will drop from 60A to 50A.

Dutch320

That would be a NEC code violation if the shore power receptacle was protected with a 50 amp breaker and you had wires rated for only 30 amps. Your shore power cord would be #10 wire for 30 amps, you would need #6 wire to be protected by a 50 amp breaker. Chances are the marina just changed the receptacle and didn’t pull new wire to the outlet, either way if it’s on a 50 amp breaker it’s a code violation. That being said if the marina just changed the receptacle and it’s still protected by a 30 amp breaker it wouldn’t be a fire hazard. 

Grahamu

Normally!!! A 50 amp 125/250 pedestal outlet is protected by a double bridged breaker limiting the amperage on each leg if one trips they both trip

Dutch320

I agree that a125/250 volt outlet would be on a two pole breaker, but if it was a 50 amp two pole breaker the wire would have to be sized accordingly . A two pole 50 amp breaker won’t trip unless one leg draws more than 50 amps, not a combined  50 amps between poles. It’s essentially two 50 amp breakers tied together. A two pole 30 amp breaker would require #10 copper wire or #8 aluminum wire and a two pole 50 amp breaker would require #6 copper wire. A fire hazard would occur when #10 wire (shore power cord) is protected by a 50 amp breaker at the pedestal. 

Grahamu

I agree if the boat has no protection, but my boat has 30 amp breakers close to the shorepower inlets and also 30 amp breakers on the panel. They would all have to fail to cause a fire hazard.

Liberty44140

Many thanks! I've got no problem with the 50 - two 30 for traveling, I have an adaptor and it really comes in handy cruising in Michigan where you get one 30 and one 50, its the continuous use for 5 months a year. 
The marina tech is supposed to call me, not sure why, but I will ask him how it is wired to the pedestal (guage), and the breaker set up on the pedestal, and then report back. Sounds like if this 50a outlet at my dock is split to two legs and they are 30a each this is actually ok?

Dutch320

Yes, if it’s a 50 amp outlet but it’s fused at 30 amps you’re good. My marina is pretty old so I only have one 30 circuit at the pedestal. Luckily have been ok with it so far 

mattie

Kinda related, I've been using these 'Cable Cuff Pro's' for a quick tie job on 30A cables.
Got them at HDepot. Diff sizes avail.
Really slick.

Dutch320

@Grahamu your boat is protected correctly. I was referring to @Liberty44140 situation, trying to give him a good argument to present to his marina for changing his setup. On my 320 and most boats I imagine, the weakest link would be from the shore power receptacle on the boat to the first point of protection (the breaker) on the boat. If something failed in that area, like melted wires, there could be a problem with improper protection.