Shore Power Adapters

R

Rob & Karen

New member
Last fall, we spent a night at a marina that had only 50A service available. Our shore power setup is 30A, so we had to borrow an adapter from the marina.

Trying to be prepared, I recently bought an adapter. On the box it cautions about 50A 125V being different from 50A 125/250V. I did not realize that there were two different types of 50A service and I am not sure if I have the right adapter. Does anyone know if one type of 50A service is more common than another? I guess to be really prepared, I should have both. But at the cost of even one, I don't think I am prepared for that.

Any information would be appreciated.

Rob
 
I don't think (I could be wrong though) that there are many if any marinas that have 200+Volt service. That would be for very big boats/ships that have full size ranges and water heaters on board. I think if the plugs fit the sockets, you should be OK.

Now all you marine electricians chime in! :shock:

Charlie
 
The only 50A plug I have ever used is at a marina a couple hours from here, so I don't know if what I have fits or not. I may call the marina tomorrow and ask.

I see that there is only one type of 30A plug and I assumed that there was only one type of 50A plug as well....wrong. I have the 50A 125/250V model. If it is commonly used, I will keep it. If not, I will probably return it.

I am hoping someone has experience with this and will know if one of them is most commonly used. If both are common, I may just return it and forget about it. They are too expensive to buy two and use them only very occasionally.

Rob
 
Rob if the 30 amp side fits your 30 amp cord then the 50 amp side should be correct. If it didn't fit I'd say you had a 220 volt adapter. A 220 volt adapter will have a different type 30 amp side than what you have on your 30 amp 110 volt cord. Hope that makes sense.
 
Marvin,

Since there is only one type of 30A plug, the 30A side is fine. My questions is about the 50A side. I have the 50A 125/250V plug, but I am not sure if that is the one I need, or if I should have the 50A 125V plug.

I guess I will need to call the marina tomorrow.

Rob
 
We've gone into different marinas that only had 50 amp service and the sockets have been different. When we stayed in San Francisco, the marina lent us an adapter... after walking down a VERY long dock back to our boat, I found it was the wrong adapter. By the time I got back to the office, it was closed. The security guard found me another adapter, and told me that they had two different 50 amp plugs in that same marina.

In the great majority of marinas we've visited, 30 amp is readily available. In places where it's been only 50, we've been able to borrow an adapter. They're not cheap, so I wouldn't be in a big hurry to buy several to cover the different types.

Best wishes,
Jim B.
 
Rob,

Since you are asking which is the most common adapter if you need to purchase one, I would purchase the 50amp 125/220 adapter to your 30amp. I have both types of 50 amp adapters but I find the 125/220 is more common if they have to put you in a larger available slip. However, if the only slips available are the 48-ft and larger, you will find the 50amp220 receptacle is more common.

They are expensive but you don't necessarily have to purchase the Marinco brand. You can find adapters from Grainger or Home Depot. They do not have the cord between the two, just a straight adapter. But for a weekend stay and the price difference, it is worth it. Then, you could consider buying both.
 
I think in all the years of boating, San Francisco was the only place where I needed to get a 50 amp adaptor from the marina.... I don't think I would ever buy that adaptor... the marina was expecting to have to loan those out...and they had plenty... they knew the problem well...

Joel
SEA3PO
 
Rob,

I realized that I did not use the proper terminology for the 50amp adapters. The 50amp 125V is probably the most common I have come across. It is provides one 50 amp leg at 125vac to one main breaker.

The 50amp 125/250V is use for bigger boats that will have a larger breaker panel. It provides two 50amp legs at 125vac each.
 
Here's something for FREE from West Marine, a very good tutorial on all the types of Shore Power Adaptors.

Quoted here for your convenience:

Shore Power Adapters
Identifying Shore Power Connections
This can be tricky, especially when you’re standing in the pouring rain with your cell phone, trying to place an order for the adapter you need in order to get plugged in. Check the charts at right carefully to ensure that you choose the correct cordsets and adapters for your boat.

Troubleshooting Shore Power
The majority of dock power troubles can be linked to two simple problems: overheating and saltwater immersion.

If you suspect a bad connection, turn off the dock power at the outlet and unplug the dock cord couplings at the outlet and boat. Inspect the male and female plug ends for signs of melting or corrosion. Inspect the outlet and the boat’s inlet for heat and corrosion damage.

Replace the connector immediately if you find signs of overheating. Be sure to inspect wire ends for signs of corrosion or overheating when replacing connectors.

Marinco suggests that many dock cord connectors are replaced unnecessarily because boat inlet and dock outlet connectors are at fault. Be sure to inspect all components with equal care.

If your dock cord connector gets dunked in salt water, disconnect quickly and rinse well in fresh water. Dry thoroughly before use.

Plugging in Power Tools With Shore Power Adapters
Shore power adapters, which allow you to plug in a variety of cords to a marine power center, must be used carefully or they could inadvertently create a shock or electrocution hazard.

When working around a boat, it’s tempting to use a shore power dockside outlet and an adapter to allow the use of a drill motor, sander, or other power tool. There are several problems with this "solution":

The only circuit protection is the 20 or 30 amp breaker on the shore power center, which will undoubtedly exceed the power rating of the cord that is plugged into it.
There’s no operator protection from a GFCI, since that would normally be found onboard the boat, and there’s no boat involved. Therefore, the operator of the power tool, while using it in a wet environment, is in danger of electrocution. In fact, shore power centers are only intended to supply power to a boat, using an approved shore power cord, and not as general purpose AC outlets.
So what’s a boat maintenance worker supposed to do to keep safe? We think there are two possible answers:

Plug the power cords into an outlet on the boat which is protected by a 15A breaker and a GFCI somewhere in the circuit.
Consider buying a portable GFCI which can be installed inline on the power tool’s extension cord.


step1.jpg


step2.jpg


step3.jpg


Hope this helps and that some will find it useful!

Joe. :teeth :thup
 
Thanks for all of the replies. It sounds like people that do alot more traveling than I do get along just fine without having their own adapter. I decided to return it and use the money for some other boat item.

Rob
 
I own the 30 amp to 50 amp 115/230 adaptor. In the hundreds of marinas we have stopped in, this is the most common 50 amp unit we have come upon. It is the one used by bigger boats, which may have 220 service, or two different 30 amp legs. We also carry a 30 amp female, with pigtails, and several hardware store adaptors, so we can go to RV 30 amps, 20 amps in Canada, and various plugs in Mexico--and other parts of the world in the past.
 
Back
Top