125/250 50amp shorepower

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Ka_sea_ta

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I should be able to figure this out but I don't want to tear into the boat to look at the configuration on the shorepower connection on the boat.

The boat has a 125/250 50 amp shorepower connection... When I look at the ac panel there is a double pole breaker that serves as the main disconnect for the ac service. One pole is the neutral the other is hot and feeds the rest of the ac circuit breakers in the panel.... My question is what happens to the other ac leg? the boat does not use 220. It's a 4 wire cord so 220 is at the boat... is the other hot input just not connected at boat? Any one else seen this configuration where 220 is supplied but only 110 is used.
 
Do you have any 220 loads? We do on our DF and Id guess your boat is wired to be 220 capable. Also, our ACs run on the "other leg" even though they are 110.
 
Do you have any 220 loads? We do on our DF and Id guess your boat is wired to be 220 capable. Also, our ACs run on the "other leg" even though they are 110.


There are no 220 loads on the boat. we don't need air cause it's up north. It's certainly 220 capable I just don't have a clue where the other leg terminates or if it just not connected. Thanks for the reply. By the way does your boat have 2 aft water tanks they appear to be about 100 gallons each? We spend a majority of our time about 15 miles west of you.
 
Our vessel has two aft fuel tanks, not water as you have.
 
My guess would be its just not connected.

They use the 240V plug and socket because its robust and common.

You should be OK pulling 50A on one 120v leg.

How do you adapt down to a marina with only a 120V 30A outlet?
 
"Any one else seen this configuration where 220 is supplied but only 110 is used."


Yes - I have seen it often. Most applications have the two legs feed different 'lines' of 110 breakers after the main breaker(s). So each leg feeds one or more sets of devices at 110 each. On many boats that we have had there is also an optional switch that can 'parallel' these spate incoming lines when a single 30 or 50 amp connection is supplied through an adaptor or directly to the boat.
 
My guess, and it's just a guess is that the other leg isn't being used. If you had a boat with air conditioning, there would likely have been a different panel which utilized both legs. If you look at the power feed cable, there may be an unused conductor at the back of the panel for the second leg. My guess is that if you pull the power plug for the boat, you will find no wire in that second leg hole. They most likely use that plug for the amperage and how common it is.

Ted
 
I should be able to figure this out but I don't want to tear into the boat to look at the configuration on the shorepower connection on the boat.

The boat has a 125/250 50 amp shorepower connection... When I look at the ac panel there is a double pole breaker that serves as the main disconnect for the ac service. One pole is the neutral the other is hot and feeds the rest of the ac circuit breakers in the panel.... My question is what happens to the other ac leg? the boat does not use 220. It's a 4 wire cord so 220 is at the boat... is the other hot input just not connected at boat? Any one else seen this configuration where 220 is supplied but only 110 is used.
this is weird.

No manufacturer would do that, and a 48 foot boat would certainly be a candidate for 2 busses of breakers.

Can you see behind where the shore power inlet is?

My guess, the boat my have originally been 50A 125. The PO may have thought about upgrading and just went ahead with replacing the cord and inlet with the 4 wire setup . This made connectivity at the dock easier and gave future options. Until you have an inlet main breaker that takes 3 poles, 2 hots and a neutral, you are stuck with one leg I think.

I just replaced my panels from 2, 30 amps to 1, 50A 125/250 and am very happy even though the cost was high. You are part of the way there, I would finish up the conversion.

That missing hot could be someplace else...but I think if it isn't in a breaker than can trip the other hot and neutral, you have a dangerous setup...so, I would make sure ASAP.
 
I just replaced my panels from 2, 30 amps to 1, 50A 125/250 and am very happy even though the cost was high. You are part of the way there, I would finish up the conversion..

Have any tips/advice/photos of the refit? We have the same configuration and just this past Friday, discussed changing from 30x2 to a single 50A 125-250 setup.
 
Have any tips/advice/photos of the refit? We have the same configuration and just this past Friday, discussed changing from 30x2 to a single 50A 125-250 setup.
not really...well could be a million things but mostly deciding what your electrical setup ultimately is going to look like.

My biggest change was to split the ac outlets into 6 distinct areas, versus port and starboad. Plus they all went to a sub panel that would be fed from shore or inverter.

Overall cost probably approached $3K, $2500 just for the panels, but worth it as the prewiring, labels, lighting and digital meters all drove up the cost. But 4 screws per panel, and start pulling wires. The panels were from Paneltronics in Miami, Fl.....picked them up at the factory as I was nearby on my winter trip. The panels they made fit my cabinet too, Blue Seas didn't and the quality is very similar, maybe better with Paneltronics.

One other tip...no matter how well you plan your system, if you can leave 2 - 4 spares for at least the DC side, it's a good thing. :banghead:
 

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My guess would be its just not connected.

They use the 240V plug and socket because its robust and common.

You should be OK pulling 50A on one 120v leg.

How do you adapt down to a marina with only a 120V 30A outlet?

This is the problem, the boat has several adapters, and a couple of different SP cordsets wired in different configurations. I just want to keep this simple and safe as possible... 50amp at the dock use the big cordset 30amp use the smaller cordset...
 
Not to dobut you, but how do you know it is the 4 wire setup and not just a 50 amp 125 cord and ends?

End molded on and labeled 125/250?

Just curious how off the beaten track this setup is/isnt.....
 
Not to dobut you, but how do you know it is the 4 wire setup and not just a 50 amp 125 cord and ends?

End molded on and labeled 125/250?

Just curious how off the beaten track this setup is/isnt.....

Yup 4 wire cordset 125/250 volt connector
 
Yup 4 wire cordset 125/250 volt connector
And not a second panel someplace to take the second hot and neutral and Sunchaser mentioned for secondary loads such as AC?

Sunchaser, do they just jumper the neutral to the second panel?
 
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Not to dobut you, but how do you know it is the 4 wire setup and not just a 50 amp 125 cord and ends?

End molded on and labeled 125/250?

Just curious how off the beaten track this setup is/isnt.....

It's an older Asian built boat. It could be so far off track you couldn't even see the beaten track with a telescope. :D
 
This is the problem, the boat has several adapters, and a couple of different SP cordsets wired in different configurations. I just want to keep this simple and safe as possible... 50amp at the dock use the big cordset 30amp use the smaller cordset...

I don't understand the problem. If you have a cord for a 50 amp 120/240 dock pedestal and one for a 30 amp 120 dock pedestal, what's the issue?

Ted
 
And not a second panel someplace to take the second hot and neutral and Sunchaser mentioned for secondary loads such as AC?

Sunchaser, do they just jumper the neutral to the second panel?

If there is I haven't been able to find it in 3 years + of ownership... I have to do a little rewiring on the inverter so It's just a few more screws and a couple more scrapes on my arms to verify what I suspect which is the manufacturer just bought 1 kind of shorepower connector for all boats and just didn't connect the other leg if it was a 120 with no additional requirements.
 
I don't understand the problem. If you have a cord for a 50 amp 120/240 dock pedestal and one for a 30 amp 120 dock pedestal, what's the issue?

Ted

Problem is where does the other leg of the 240 terminate...
 
Problem is where does the other leg of the 240 terminate...

Most likely in the boat side plug. The boat side receptacle just has three wires to it and the fourth hot spot is just empty with no wire connected to it.

If you think it might be disconnected in the power cable just plug the cable in at the dock, turn the breaker on and meter the boat end of the cable to see if you have two hot legs.
 
I should be able to figure this out but I don't want to tear into the boat to look at the configuration on the shorepower connection on the boat.
.

If it were me I'd want to know what I have...
Check boat end of cord to see if 1or 2 hot legs
Then 4 screws to pull boat inlet and check how many legs are wired...and check for any sign of overheating then tighten them all while you are at it.
If 2 hot legs I'd be looking behind the panel to figure it out.
But that's just my curiosity to know what is there...I can't imagine any mfg or owner spending the $ when it's way overkill???
 
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Yup 4 wire cordset 125/250 volt connector

The Eagle was wired for 120 volts 50 amps, one leg, 3 wire. However I installed installed a 220 volt plug and shore power cord as that was the most common dock power for our size boat. Also in the future might change to 220 volt in the future. The second leg was not connected.
However 2 years ago we retired and insurance and marina would not allow to heat the boat with the webasto diesel heater while away from the boat. So we had a separate electrical panal installed, 120 volt, 50 amp, specifically for 3 addition electrical heaters. So the boat is 120 volt 50 amps, except for 3 addition heaters used only when away from the boat. Cost 1000.00 for the new panel, wiring and heaters and was the cheapest and simplest way.:thumb:
 
I would start by looking at the back of the boat power inlet receptacle. If the cable is 3 wire, you're done. Nothing is attached to the second leg. If you have 4 wires, time to look at the back side of the breaker panel to see where the 4th wire goes. My bet is that a previous owner changed the receptacle from 50 amp 120 to 50 amp 120/240 and there are only 3 wires in the cable going to the receptacle.

Ted
 
Can you post a clear picture of your AC bus? If you have two AC load groups originating from the bus, it should be easy to tell.
 
I should be able to figure this out but I don't want to tear into the boat to look at the configuration on the shorepower connection on the boat.

The boat has a 125/250 50 amp shorepower connection... When I look at the ac panel there is a double pole breaker that serves as the main disconnect for the ac service. One pole is the neutral the other is hot and feeds the rest of the ac circuit breakers in the panel.... My question is what happens to the other ac leg? the boat does not use 220. It's a 4 wire cord so 220 is at the boat... is the other hot input just not connected at boat? Any one else seen this configuration where 220 is supplied but only 110 is used.

It's very difficult to see how your boat is wired over the Internet. Several people have already made several guesses and any one of them might be right.

Taking the electrical inlet loose and seeing if all the wires are hooked up is a good start, but if they are, It's time to call in a marine electrician if you can't figure it out yourself.
 
"Any one else seen this configuration where 220 is supplied but only 110 is used."


Yes - I have seen it often. Most applications have the two legs feed different 'lines' of 110 breakers after the main breaker(s). So each leg feeds one or more sets of devices at 110 each. On many boats that we have had there is also an optional switch that can 'parallel' these spate incoming lines when a single 30 or 50 amp connection is supplied through an adaptor or directly to the boat.


Our is like that. No 220V appliances. 50-amp shorepower in with a double-pole breaker, and then the main AC panel is immediately divided into two "lines" -- clearly marked, 1 and 2 -- so either leg of the service only runs about half of the house 110V loads. One fridge on each line, one AC on each line, water heater and cooktop on one, and microwave and outlets on the other, etc.

In our case, we also happen to have a switchable volt meter and ammeter on the panel, so we can get a little insight into which loads are doing what on which line (leg).

-Chris
 
Well figured this out... The builder didn't connect the 2nd leg of the AC at the shore power receptacle.... Must have got a deal on the 125/250 connector...
 
Kinda figured that would be the case. 50 amp 125/250 volt receptacles are far more common in the US than 50 amp 125 volt receptacles.

Ted
 
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