50 amp to 30 amp shore power

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larman

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Location
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Livin The Dream
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Sea Ray
So my new marina does not have 50 amp service and my boat requires it. I do have a Marinco Shore Power EEL "Y" Adapter but the 30 amp connectors are female and I need male connections. I really do not want to shell out $300 for a new adapter if I don't have to. Are their any other options for connections?
 
What do the Y female connectors connect to? Sounds like maybe your boat has two 30 amp inputs. If so, go on craigslist and buy a couple of 30 amp cords. They are quite common on craigslist and usually really cheap.
 
My boat has a single 50amp male connector. My adapter would connect to my 50 amp male but the two 30 amp ends are female and I need male ends to connect to the power pole. I am connecting to a power pole with two 30 amp female connectors. Your idea is a good one. I have a bunch of cords on board will look into the two 30 amp cord suggestion. Thanks!
 
Replace the 50amp boat socket with a 30amp socket or buy the proper Y adapter that allows you to plug into two different 30amp outlets.
 
Is it 50 amp 120 volt or 50 amp 240 volt? This makes a huge difference.

Ted
 
Two basic questions please. On your boat, how many shore power connections do you have. Are they 30amp or 50amp?
The dock service, 120vt or 240vt?
 
larman said:
My boat has a single 50amp male connector. My adapter would connect to my 50 amp male but the two 30 amp ends are female and I need male ends to connect to the power pole. I am connecting to a power pole with two 30 amp female connectors. Your idea is a good one. I have a bunch of cords on board will look into the two 30 amp cord suggestion. Thanks!
Click to expand...


I can't fathom why you have a Y with two 30 amp female ends, if you don't have any 30 amp inlets. Sell that thing, it's of no use to you and should be easy to sell as there are plenty of boats with two 30 amp inlets.



Sorry to break the news, but I think that if you have a 50 amp 250 volt inlet (likely) you need a smart-Y with two 30 amp male ends and a 250 volt 50 am female end. If you have a a 125V 50 amp inlet (rare), you need an adapter with 250V 50 amp female and 30amp male ends.
 
A Y cable with 2 female ends for the dock and it will give you 1 50amp to the boat.
 
You need to know whether your boat gas any 250v demands 'cus if u do, u will definitrly need a smart Y (yup, the expensive one) to connect 2 x 30 Amp dock receptacles to your 50A 125/250v cord set to you boat in order to get both the L1 & L2 legs needed for 250v. You will only get 30 A total so some load management will probably be required especially AC units running with hot water heaters and stove/oven.

Some boats are set up with 2x 30 A circuits fed by a single 50A cord set split to the 2 x 30A receptacles at the boat (which is why u may have your 50A/250v male to 2x30A/125v female splitter). If that is the case then 2x 30A cords will work. I would be very reluctant to purchase used 30A cords. They are the commonest cause of boat fires especially at the connectors. If they have been dunked in salt water - even worse. Just not worth the risk imo. Those of us who cut the ends off existing cords to use Smart plugs are usually surprised how much of the cord has been damaged.

Finally if your boat is the rare one that only needs 125v, there is a 30A/125v male to 50A/250v female pigtail that connects the hot leg supply to both L1 & L2 legs of the 50A cord (so u can't run 240v devices and 30A max.)

I understand but haven't confirmed that there are virtually no marinas anymore that have 50A/125v dock service
 
Flatswing said:
I understand but haven't confirmed that there are virtually no marinas anymore that have 50A/125v dock service
Click to expand...

Correct. Our previous marina implemented an insurance-mandated no splitters / adapters rule for non-transient boats, so they put in a pair of 50A 125V outlets for us (we've got 2x 50/125 inlets, so normally we use a splitter from a 50/250 or pigtails from 2x 30A).
 
OldDan1943 said:
A Y cable with 2 female ends for the dock and it will give you 1 50amp to the boat.
Click to expand...


On power cords, female connectors are always outlets and male connectors are always inlets. That Y would only work to split a 50A 250V dock outlet into two 30A 125V outlets. The OP needs the opposite style Y.
 
Yes I believe it is a 50amp 250V. Ouch smart Y sounds expensive.
 
This season I went to a marina in Catskill NY they had 30 amp power. They lent me this and it worked fine. I guess I will have to purchase one.

WBP_YQ230_PRODIMAGE_1200.jpg
 
ok, this is going to get a bit complicated. Your boat is 50a 125/250v. This means you have both 120v and 240v capability on your boat. The first thing we need to know, do you have any 240v applications? This can be confusing as well. For instance, I have a 240v dryer on board but I use a step up transformer, which means I only use one 120v leg to run my dryer at 240v. If you have no 240v applications then any two 30 amp sockets will work. If you have a 240v application you will need the adapter and two dockside outlets that are in opposite phases or your 240v applications will not work.

In other words, just buying the adapter may or may not solve your problems.
 
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larman said:
So my new marina does not have 50 amp service and my boat requires it. I do have a Marinco Shore Power EEL "Y" Adapter but the 30 amp connectors are female and I need male connections. I really do not want to shell out $300 for a new adapter if I don't have to. Are their any other options for connections?
Click to expand...

rslifkin said:
Correct. Our previous marina implemented an insurance-mandated no splitters / adapters rule for non-transient boats, so they put in a pair of 50A 125V outlets for us (we've got 2x 50/125 inlets, so normally we use a splitter from a 50/250 or pigtails from 2x 30A).
Click to expand...


Seeking clarity first: Your boat has two 50A/125V inlets. (Not 2x 50A/240V.) You have no 240V appliances on board. You have used two 30A-to-50/125V pigtails previously.

??

What exactly is the problem at the new marina? Why doesn't the pigtail solution work?

-Chris
 
larman said:
My boat has a single 50amp male connector. My adapter would connect to my 50 amp male but the two 30 amp ends are female
What you are describing is a y connector with a female 50 amp at one end and two female 30 amps at the other end. If you think about this configuration you will be hard-pressed to find anything that could connect to this. Any connector or shore power cord has to have mail at one end and female at the other. You may want to go back and check the port on your boat which should have the mail connection.
Click to expand...
 
My guess is that the PO bought a 50a splitting to 2 30a adapter by mistake and When he sold the boat he left it realizing he would never need it on his new boat either. The new owner doesn’t know that it’s a mistake and scratches his head trying to figure out where it goes.
 
tiltrider1 said:
My guess is that the PO bought a 50a splitting to 2 30a adapter by mistake and When he sold the boat he left it realizing he would never need it on his new boat either. The new owner doesn’t know that it’s a mistake and scratches his head trying to figure out where it goes.
Click to expand...


I suspect that happened to the PO of my boat. My boat came with one of those Y adapters that does not fit my boat too.
 
PO may have had the adapter from a previous boat and transferred it before realizing that it wasn't useful for the new boat.

Personally, I'd say all of those 50 -> dual 30 adapters belong in the trash. Unless they've got 30A breakers in the splitter (none I've seen do), they're dangerous, as the 30A output legs, 30A cords to the boat and 30A boat inlets aren't properly protected (the 50A pedestal breaker can't safely protect the 30A rated gear).
 
rslifkin said:
PO may have had the adapter from a previous boat and transferred it before realizing that it wasn't useful for the new boat.

Personally, I'd say all of those 50 -> dual 30 adapters belong in the trash. Unless they've got 30A breakers in the splitter (none I've seen do), they're dangerous, as the 30A output legs, 30A cords to the boat and 30A boat inlets aren't properly protected (the 50A pedestal breaker can't safely protect the 30A rated gear).
Click to expand...

and that is why we have the internal breakers.
I have been using a 50amp to 2 30amp splinters for many years with no problems.
 
OldDan1943 said:
and that is why we have the internal breakers.
I have been using a 50amp to 2 30amp splinters for many years with no problems.
Click to expand...

The internal breakers protect the wiring downstream of them (the panel and if you have separate inlet breakers, the wiring from them to the panel). But a fault in the inlets or shore cables is still unprotected.
 
I don't know why boat manufacturers often have a 50a/250v option only. That's what I have on my Mainship, and at times, it's a PITA when I cant get 50a or 2 30a out of phaze.


What I did, was add a 110v/15a plug that powers and independent charger, which will work with any marina set up, just to keep the batteries charged. If I don't need the 220v appliances, heat or air, I can get by fine, with minimal power use.... occasional coffee maker and microwave. That's what I have for my current short power .... no 50a there.
 
Seevee, if you don't have any 250V loads and your boat is wired as 2 independent 125V / 50A feeds to the 2 halves of the panel (from the 2 phases of the 125/250V inlet), you can use a non-smart adapter to draw from 2x 30A dock outlets without worrying about whether they're on opposite phases or not.

If you have any 250V loads and you do this (and get 2 outlets on the same phase), they'll just have 0 volts (so they won't work), but the 125V stuff will work fine.
 
rslifkin said:
The internal breakers protect the wiring downstream of them (the panel and if you have separate inlet breakers, the wiring from them to the panel). But a fault in the inlets or shore cables is still unprotected.
Click to expand...


Sorta...the boat can't draw enough to protect the shore power cord because the panel has 30A breakers and for a short in the shore power lines the breaker on the pedestal protects itself.


Doubt the manufacturers wold sell the adapters if it was a big issue.
 
psneeld said:
for a short in the shore power lines the breaker on the pedestal protects itself.
Click to expand...

That's what should happen. But when you've got a 30 amp shore power cable (10ga) protected by a 50A pedestal breaker, a short could pull enough current through it to cause a meltdown before the pedestal breaker trips.
 
rslifkin said:
That's what should happen. But when you've got a 30 amp shore power cable (10ga) protected by a 50A pedestal breaker, a short could pull enough current through it to cause a meltdown before the pedestal breaker trips.
Click to expand...
Same can happen with a 50A cord...plugs melt all the time on all cords and breaker combos....


This is borderline fearmongering...as I said, even manufacturers know that a short in the actual cable is a very low threat situation.


And so many boaters live with it.
 
Yeah, I'd worry more about a short at the inlet than in the cord itself. But still, it's bad practice to leave that stuff unprotected.

And there's a difference between a meltdown from too much resistance (where a breaker won't save you) and a meltdown from too much current draw (where a breaker will help). Might as well at least take care of the easy one to protect against.
 
I just don't see any grave danger in a 50A 125/250 cord being split into 2 30's.


The short splitter is the only "under-protected" wire and is aboard where it probably has little or no real threat to it.


Just overworrying in the big scheme of boating threats....unless I read it wrong...they are UL approved so not sure why the distrust.
 
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