50amp plug vs two 30 amp plugs

R

risingson

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My boat has 2 - 30 amp cords. My dock has only a 50 amp plug. I have been using a 50 amp splitter to two 30 amp connections. What are the pros and cons by using the 50 amp splitter? should I have the marina change my dock box to two 30 amp plugs? Or leave as is.
 
That is what I've had for 15 years never a problem. I have 30 amp. breakers in the boat so the boat is protected. Everyone on this pier in the marina has the same (50 boats) all use 2 30 amp. cords.
 
You lose 5 amps per side. Unless you are pushing the envelope on consumption, you'll be fine. My homeport has twin 30's. I've visited places as JimPend describes. In the dead of summer, I saw no difference.
 
quote:
Originally posted by KiDa

You lose 5 amps per side. Unless you are pushing the envelope on consumption, you'll be fine. My homeport has twin 30's. I've visited places as JimPend describes. In the dead of summer, I saw no difference.

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I'm not so sure about that. On my old boat, we had 2 - 30 amp plugs as well and we had the choice of using 2 - 30's or the 1 -50 using a splitter. Our boat had 2 circuits, one powered the 3 AC units and when running, they needed a full 29 amps. If we had lost 5 amps using the splitter, we never could have run all 3 AC units.

Remember, volts times amps = watts. 240 volts x 50 amps = 10,200 watts. 2x30 amps = 60 amps x 120 volts = 7200 watts.
 
If he had 3 AC units on one cord the boat was wired wrong but it wouldn't blow the 50 amp breaker he would still have 20 amps on the other cord.
 
quote:
Originally posted by JimPend

If he had 3 AC units on one cord the boat was wired wrong but it wouldn't blow the 50 amp breaker he would still have 20 amps on the other cord.

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Agree. I have a single AC and the stove on one leg. The water heater and microwave on the other.

Those are my largest power draws. The boat would catch fire if wired any other way.
 
I'm an engineer, so I know what I'm talking about. Also a 40 year boater.
 
Mike I see no reason to swap it out unless you are having issues with the adapter staying connected. The other way around it more of an issue where the boat needs a 50 and you are feeding two 30's. You are fine and have been for years why chance now? Just keep a penny on you ice tray and you will be fine:)
 
I thought that a 50 amp plug is 220v and a 30 amp is 110v. Which I thought means 50 amps at 220v would equal 100 amps at 110v. So plugging 2 - 30 amp cords (with adapter) into a 50 amp socket would actually give you more power, not less.
Am I wrong?

Walter
 
Not all 50AMp is 220v, there is 125v 50 Amp (AKA Watch Hill)

But with that said I run on 50amp 125v with two 30 amp cords at Watch Hill and never have a issue.
Been there on the hottest days, running everything with no issues other than the electric being dated and faulty and crapping out for other reasons.
 
Not all 50AMp is 220v, there is 125v 50 Amp (AKA Watch Hill)

You sure about that Dave, can't see how anything could work on my boat since it needs 220v.
 
I am positive. I carry 2 adapters, One 50AMP 250v and one 50AMP 125v.
You should know, you had a 34C with two 30amp cords that you used to plug into a 50amp at watch hill.
Your boat can only fit in 9 slips there with 220v service, the others are 125v.
 
quote:
Originally posted by JimPend

If he had 3 AC units on one cord the boat was wired wrong but it wouldn't blow the 50 amp breaker he would still have 20 amps on the other cord.

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We had a Carver 3807. It came from the factory with 2 separate circuits. All 3 AC units were on one circuit by themselves. Everything else was powered by the other circuit. There was absolutely no cross over between the 2 circuits. Each circuit had its own voltage and amp meter so we could monitor electric usage. The 3 AC units needed a full 29 amps. Many times we had all 3 units working and using more than 20 amps on the other circuit, especially around dinner time when the oven was going, water heater heating and other household usage easily running 25+ amps...well over 50 amps total.
 
quote:
Originally posted by CurrentSea

Not all 50AMp is 220v, there is 125v 50 Amp (AKA Watch Hill)

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Yes, there is 50amp - 120 volt out there but it's few and far between. I was talking to a buddy the other day who made the great loop a few years ago, meaning he docked at many, many marinas over the course of 9 months. He said he never saw the first 120v-50amp service, they were all 240-50.
 
I will touch my toe in the waters here.

The Ampere rating is on the supply side of the circuit and is the Max. that the circuit will or can supply.

I have 125 VAC at a 50 amp rating and this supplies only 50 amps to my boat thru a splitter. How it gets "split" once in the boat is thru the wiring configuration thru each 30 amp circuit. It may end up being 25 and 25, it may be 30 and 20. Each 30 amp cord will not exceed its rating if wired correctly thru breakers.
If you have a very high demand it is better to use the two 30 amp cords.
Assuming that the power distribution is correct on the inside.
 
TJM, what you have is rare. I've never seen a 125V-50 amp service and most people haven't. Obviously, your marina supplies it and I'm sure there are other marinas scattered around the county that do as well, but few and far between.
I'm willing to bet $5 that the OP has 240v-50 amp which is a different animal completely. That will supply twice the wattage of what you have.
 
There are only 125v-30 amp and 50 amp connections in my marina.
There certainly are some, but 220-240v connections are more rare in my area...
 
The OP has a 50 Amp 240 Volt on the dock which when split provides two 50 amp 120 Volt lines. I spoke with him yesterday and he has since replaced his adapter and made a box/housing to protect the connections.
There are many different configurations for marine power and while it is true that years ago 50 amp 125 volt was somewhat common however it was a different plug and would be hard to confuse.
 
quote:
Originally posted by Audrey II

The OP has a 50 Amp 240 Volt on the dock which when split provides two 50 amp 120 Volt lines. I spoke with him yesterday and he has since replaced his adapter and made a box/housing to protect the connections.
There are many different configurations for marine power and while it is true that years ago 50 amp 125 volt was somewhat common however it was a different plug and would be hard to confuse.

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My 1988 Carver that I mentioned above, came from the factory wired to accept 125v-50 amp. However, the previous owner, having lots of problems finding 125-50 service, had special shore power cords made up...125-50 boat side, female ends with 125-30 dock side male ends. We used those power cords for many years.
 
Likewise... My '90 Carver is wired 2 x 50amp, 125v.
No problem here... And we use reducers to go down to 30amp receptacles, as req.
 
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