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steve77 · 19-07-2015, 03:48

A boat came in to Horta with large power requirements - 50 Amps 240 Volts in the US and we are trying to connect to the European 230 V shore power outlets.

The shore power pedestals here have four 16 Amp outlets. We discovered that these outlets contain multiple phases of the power distribution system so that the voltage between two outlets (at least the two I checked, I did not try all combinations) is 400 Volts.

We made up an adapter pigtail to allow them to plug into one of the 16 Amp receptacles, but it really limits them as to what they can run onboard. My question is, how can we make a Y-adapter for this boat? All I can come up with is to wire two 16 Amp plugs in parallel to the feed the 50 Amp plug that connects to the boat. Then it becomes a safety issue to check the pedestal with a voltmeter to ensure you are plugging in to two 230 Volt receptacles that are in phase, with the voltage between them at 0 Volts.

Any thoughts?

Cheers!

Steve

DSDman · 19-07-2015, 13:11

Seems like it would just be easier to install a 50 amp cb and outlet from the shore side. Assuming of course the supply wiring is rated to handle that much amperage. Since there are 4 16 amp plugs it would seem so but you couldn't use any of the other plugs if that boat was pulling all 50 amps worth from that one circuit. I don't think the amperage doubles like the voltage. If you do what you suggested you would end up with 480 volts at 16 amps still. Which is not good. Disclaimer...I am no electrician.

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smac999 · 20-07-2015, 00:53

50a 240v is pretty normal for a 50'+ north American boat. certainly not "huge" power requirements. (I was on one last week that kept blowing his 50a at the dock..)

hubble makes some "smart Y" cables that will check the phase when trying to plug a 240v boat into two 120v plugs. and decide if it'll let power though or not (circuits in the Y) maybe they make plugs that can check 230 phases. but I haven't looked.

edit: looks like the only make 2 and both for north American power
http://ecatalog.hubbell-wiring.com/p.../y.pdf&Page=26

you'd need something like the first one, but have it check for in phase 230v instead of out of phase 120v. no idea if this product exists. maybe they can custom make you one for a few grand...

how are you dealing with freq?... are they aware they are only getting 50hz when plugged in?

if you can't get one of these "smart Y's" that will work, then you'd have to manualy test each pedestal and know what you are doing when you plug in. or risk major damage.

steve77 · 20-07-2015, 02:37

SMAC999 - yes, I looked for commercially available units and could not find any. When I saw Marino's reverse Y that checked for phase agreement between the two legs, I thought I had found the answer. But it won't work for our application.

Yes, they are well aware of the 50 Hz power here. Most of their load is resistive - water heater, electric stove, so it's not an issue. The other components are rated for 50/60 Hz.

Maybe you have different friends than I do, but this is the first boat I have been on with a 12 kVA isolation transformer. That's a fair chunk of power, and it's why I say "large" power requirements. There are certainly boats out their with lots of electrical components, but the norm is a little smaller.

Yes, right now manually testing each pedestal is the only solution we have. I was trying to get a sanity check on the idea to see if anyone sees anything wrong with it.

Anybody know another way to do this?

Cheers!

Steve

woodenboats · 20-07-2015, 12:33

As far as I'm informed there is no such thing as a 50A 230V Connector at least in the EU. Big boats use a "CEE" three phase 400V 32A or 63A Connector.

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svlamorocha · 20-07-2015, 13:16

Quote:

Originally Posted by steve77

A boat came in to Horta with large power requirements - 50 Amps 240 Volts in the US and we are trying to connect to the European 230 V shore power outlets.

The shore power pedestals here have four 16 Amp outlets. We discovered that these outlets contain multiple phases of the power distribution system so that the voltage between two outlets (at least the two I checked, I did not try all combinations) is 400 Volts.

We made up an adapter pigtail to allow them to plug into one of the 16 Amp receptacles, but it really limits them as to what they can run onboard. My question is, how can we make a Y-adapter for this boat? All I can come up with is to wire two 16 Amp plugs in parallel to the feed the 50 Amp plug that connects to the boat. Then it becomes a safety issue to check the pedestal with a voltmeter to ensure you are plugging in to two 230 Volt receptacles that are in phase, with the voltage between them at 0 Volts.

Any thoughts?

Cheers!

Steve

1) Are you sure that ALL on board are 220V/240V loads (which in the US would usually be fed by two live/hot wires, each of them 180 degrees away form each other and 120V away from earth) and you do not have any 120V loads that in a US boat would be fed by one of the hots and a neutral)

2) Are you sure that the boat is properly wired to ABYC standards, ie no connection of green wire to (what is supposed to be) AC Neutral wires onboard?

If the answer is YES to both questions then keep going, otherwise stop right there because stuff is going to break and people may get hurt.

I take as a given that there are no inductive loads ie motors, that would be sensitive to the change in frequency.

You said you will check that the two outlets that you are going to connect in parallel are indeed fed by the same phase and have same polarity, ie voltage between L in one outlet to L in other outlet is at most a fraction of a volt, and same for N and N.... So far so good

Also make sure that the two shore outlets belong to the same circuit in the marina installation.. Otherwise someone could get killed if they turn off a breaker to work in one of the circuits, just to get zapped when you plug in your Y adapter and backfeed the "disconnected" circuit. This is the golden rule of never "paralleling" two circuits downstream of the panel where they are born..

Note that the American boat will most lilely be wired to take two hots (call them L1 and L2) that are 180 degrees away form each other and 120V away from earth (one going each way). Now you will feed one of them with the N from shore and the other one with one of the Ls from shore. So far so good. Thw problem is that there may (or MUST) also be some 120V loads (light or fan in the oven, wall outlets, etc) that are connected between one of the two hots and a white "neutral" wire onboard the boat. In your "jury rigged" setup that "neutral" wire will not be connected to anything ashore , hence you will have what is called a "broken neutral" and it will be very easy to expose those 120V loads to almost 240V with catastrophic consequences.

Underlying all this is that the combined 120-240W wiring system you find in the US relies on having two 120V hots phased 180 degrees away form each other. Two hots give you 240V, hot to neutral gives you 120V.

In Europe you will most likely have three hots that are 120 (not 180) degrees away form each other and 220-240V away from earth, which is makes it impossible to make the combined US system delivery both 120V for outlets and 240V for heater, etc) at the same itme. In Trinidad ( at least Crew´s Inn) they have 3-phase systems but each hot is 127V away from neutral and earth, hence you can make a proper 4-wire connection between that boat and shore and get 127V in the 120V circuits and 220V (= 127 x 2 x cos 60 degrees) into teh 240V circuits.

Having said all that, my recommendation is that if you or the owner need to ask about it you probably should not be doing it. The owner can buy an isolation transformer that will do everything that is required except the frequency, and do it safely.

Mishiwa · 20-07-2015, 17:15

Hello Steve,
from the description of the problem a would assume that the feed from a main board at the marina would be 3Phase 360/400V in a Y (star) configuration, and then 1 phase taken at each pillar to supply 240V to the individual boats, by connecting 1 phase and ground/earth to the 16 A terminal. The only solution I can suggest is to split the boats requirements into 2 separate feeds, eg 1 for cookers, lights, instruments and separate one for aircon. One of them would have to bypass the isolation transformer. Hope this helps

smac999 · 20-07-2015, 22:18

Quote:

Originally Posted by svlamorocha

1) Are you sure that ALL on board are 220V/240V loads (which in the US would usually be fed by two live/hot wires, each of them 180 degrees away form each other and 120V away from earth) and you do not have any 120V loads that in a US boat would be fed by one of the hots and a neutral)

.

it probably has a 240v in center taped output isoloation transformer. since the boat is already hooked up and working. but only with 16a.

otherwise you can't really do it.

steve77 · 21-07-2015, 03:03

SV lamorocha - First, thanks for responding. Not many people have been willing to weigh in on this one.

Second, the idea of checking to see if the two "in-phase" receptacles are on the same circuit had not occurred to me. This is the type of input I was looking for - things that I had not considered. This is great advice.

Third, I didn't emphasize it in one of my earlier posts, but this boat has a 12 kVA isolation transformer already installed. It solves a lot of issues that you raised. However, it does nothing to solve the issue of how to connect shore power.

Cheers!

Steve

Nicholson58 · 21-07-2015, 20:34

Quote:

Originally Posted by smac999

50a 240v is pretty normal for a 50'+ north American boat. certainly not "huge" power requirements. (I was on one last week that kept blowing his 50a at the dock..)

hubble makes some "smart Y" cables that will check the phase when trying to plug a 240v boat into two 120v plugs. and decide if it'll let power though or not (circuits in the Y) maybe they make plugs that can check 230 phases. but I haven't looked.

edit: looks like the only make 2 and both for north American power
http://ecatalog.hubbell-wiring.com/p.../y.pdf&Page=26

you'd need something like the first one, but have it check for in phase 230v instead of out of phase 120v. no idea if this product exists. maybe they can custom make you one for a few grand...

how are you dealing with freq?... are they aware they are only getting 50hz when plugged in?

if you can't get one of these "smart Y's" that will work, then you'd have to manualy test each pedestal and know what you are doing when you plug in. or risk major damage.

We have the Hubbell smart Y thing. It checks phases when you plug into two 30 amp 120 VAC. If the phases are correct, you get a green light. If green, plug in the 50 amp cord and get 240 out. It also has a built-in breaker. Most dock side power is 240 split to 120 circuits. If the electrician did his job correctly, the phases will be re-combined correctly with the Hubbell Y. Pay attention to your demands though.

svlamorocha · 23-07-2015, 05:42

Quote:

Originally Posted by Nicholson58

We have the Hubbell smart Y thing. It checks phases when you plug into two 30 amp 120 VAC. If the phases are correct, you get a green light. If green, plug in the 50 amp cord and get 240 out. It also has a built-in breaker. Most dock side power is 240 split to 120 circuits. If the electrician did his job correctly, the phases will be re-combined correctly with the Hubbell Y. Pay attention to your demands though.

This is dangeous advice for a US boat going to Europe. Those Y adapters are designed for US shore wiring that is different.

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Nicholson58 · 24-07-2015, 16:33

Quote:

Originally Posted by svlamorocha

This is dangeous advice for a US boat going to Europe. Those Y adapters are designed for US shore wiring that is different.

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I would prefer to see the OP use a piece of well protected gear than to hand make a combiner with plugs & wire. Read the original post.

There are lots of sources for how to deal with European power. Most also recommend an isolation transformer. Our boat was set up for world cruising with Isolation and alternate choices of 120 or 240 input. There is nothing on the boat that is hurt by 50 cycles. All gear & electronics is new, LED low power draw - also a help. We are set up for 50 amp but draw far less.

johnbpedersen · 15-06-2022, 05:58

Hi Steve

Did you ever get this solved. We are now in Palma with a 50’ Privilege Catamaran. In the States, connect to 240V 50amp. Our boat is equipped with an isolation transformer and 2 Victron Combi units - one for 230V and one for 120V.

I want to be able to connect to two 32amp recepticals on the shore to supply the boat with 230V at 63 amps.

Are there Y adapters for this?

Thanks

John

smac999 · 15-06-2022, 22:54

I'm guessing you have RCD dock beakers over there. they will not parellel they will just trip. it will only work if you find in phase power with no rcd breakers.

just noticed I replied to a 7 year old thread......