Plugging into two 16 amp sockets to get 32 amp

[Hobiehobie]

Hi clever forum. I have a US boat currently in UK wired for 120V 50AMP supply. I have a stand-alone step down transformer that we use in Europe so we can plug into the 240V shore-side supply. (We fully understand the 50/60 Hz difference which makes a few of our electrical appliances non functioning in Europe). In EU most shore side pedestals only have 16 amp outlets, very few have 32 amp. Question is, can we use a splitter to parallel plug into two 16 amp outlets to get 32 amp service. Our cables going to the step down transformer are rated for 32 amp. I think there may be an issue in making sure the two 16 amp outlets used are in phase (?) but I am too much of an electrical novice to understand that, or solve for it if it is an issue. Can you help?

[Constellation49]

You should verify you have 120v/50amp service presently. This is highly unlikely, it may be you have 240v/50amp.

European 240v is on one leg, North America 240v is supplies via two legs at 120v please reference photo.

I recommend first totally understanding the differences between 120v, 240v NA and 240v Europe.

[ranger58sb]

Originally Posted by Hobiehobie

In EU most shore side pedestals only have 16 amp outlets, very few have 32 amp. Question is, can we use a splitter to parallel plug into two 16 amp outlets to get 32 amp service. Our cables going to the step down transformer are rated for 32 amp. I think there may be an issue in making sure the two 16 amp outlets used are in phase (?) but I am too much of an electrical novice to understand that, or solve for it if it is an issue. Can you help?

No clue whether possible or not, but... I think the word "splitter" would be inaccurate relative to your intentions.

You'll know here in the US, it's possible to use a splitter from a 50A/250V shorepower source to feed two 30A/125V cables to a boat.

The process of combining two 30A/125V sources into a single 50A/250V feed to the boat... is sorta reverse from the idea of "splitting" the source...

Marinco's product for that is called a Smart Y, and I think some other brand might actually call it a Reverse Y. No clue if something like that could be relevant to what you're hoping to do, though...

-Chris

[noelex 77]

If your step-down transformer is capable of delivering 32A @ 120V, the European power supply of 16A @ 240V should be converted by the transformer to close to 32A @ 120V (there will be some power loss in the conversion so around 30A is more realistic).

[GordMay]

See our earlier discussions:

“European power - 32A from two 16A outlets” ➥ https://www.cruisersforum.com/forums...ts-149692.html

“32a 230v shore power inlet on 16a marina supply?” ➥ https://www.cruisersforum.com/forums...ly-272875.html

[s/v Jedi]

I assume the 32A at 120V that you get when transforming a 240V 16A is not enough and you really need 50A instead of 32A?

I agree with noelex that this is unlikely but in case it is: no, you can’t combine multiple 16A outlets.

In Europe the feed is normally 3-fase power and each 240V leg is used to distribute power over the legs.

You need to live with 32A or find marinas with the 240/32A outlets where you can make a 120/64A is you have a transformer that can handle this, which is unlikely as well.

[Phyrcooler]

Originally Posted by noelex 77

If your step-down transformer is capable of delivering 32A @ 120V, the European power supply of 16A @ 240V should be converted by the transformer to close to 32A @ 120V (there will be some power loss in the conversion so around 30A is more realistic).

^^^^ This right here. As noted, there might be a small loss in conversion through your transformer, but as I understand, energy capable of being delivered (watts) is the same.
16x240=3,840 watts
32x120=3,840 watts

So, it’s actually down to your transformer.

[s/v Jedi]

Originally Posted by Phyrcooler

^^^^ This right here. As noted, there might be a small loss in conversion through your transformer, but as I understand, energy capable of being delivered (watts) is the same.
16x240=3,840 watts
32x120=3,840 watts

So, it’s actually down to your transformer.

Keep it at 3.6kW. It’s officially for 230/115V.

US 115V 30A and EU 230V 16A : 3.6kW

US 115V 15A regular outlet: 1.8kW

[traveller1945]

DONT EVEN TRY IT

I'm not an electrician but I understand that when the shoreside box is initially wired they will have tried to balance the load across all 3 phases.
You choose to cross connect any 2 random socket outlets, they MAY be from the same phase and your idea will work. But next time you choose different socket outlets which are NOT from the same phase you are going to have an almighty big bang, possible fire and possibly personal injury. Without opening the shoreside box and inspecting how it is wired, you aren't going to be able to ascertain which phase was used for each socket. I suggest you don't attempt this.

[Hobiehobie]

Thanks Forum. Now I get it. If I use the standard shore power 16 amp 240V with my step down transformer I am actually getting close to 32 amps @ 120V, with a bit of a loss. This is plenty for our boat, particularly as the need for air conditioning is not that high in the Outer Hebrides of Scotland and Norwegian Fjords! Thanks for all your thoughts and expertise.

[s/v Jedi]

Originally Posted by Hobiehobie

Thanks Forum. Now I get it. If I use the standard shore power 16 amp 240V with my step down transformer I am actually getting close to 32 amps @ 120V, with a bit of a loss. This is plenty for our boat, particularly as the need for air conditioning is not that high in the Outer Hebrides of Scotland and Norwegian Fjords! Thanks for all your thoughts and expertise.

Indeed. Consider it the standard 120V 30A shore power outlet. I have seen portable transformers with that same yellow outlet on it.

[SV Coronado]

We cruised the Med with a 120V boat and a transformer, equipped with both 50A 120V and 32A 240V outlets. As others mentioned, I used a 16A to 32A adapter when a 32A connection wasn't available. I have Victron gear that allows me to limit the amount of power I draw from shore. This is a useful safety feature because it prevents me from pulling more than 16 amps through my 32A connection. I don't know what brand of equipment you have on your boat, but you should check the manual to see if it has the same capability.

Slightly off topic, but when I upgraded to LiFEPO4 batteries and a larger inverter, I removed the transformer from the house circuit and replaced it with a battery charger that supports 240V. So now, when I plug into my 32A 240V outlet, I'm only charging my batteries; everything inside the boat runs off the inverter. This solves my frequency issues. Sure, I'm limited to the 5 kVA of my inverter, but we spend most of our time at anchor and are used to living with this slight limitation.

[paul2884]

That sounds like a really bad idea (and probably would just trip the RCD in the pillar, the load would need to be perfectly ballanced. Any inballance in the voltage or current would trip the RCD). Not to mention the excitment if you plug it into a diffrent phase 400v short circuit probaly around 1000A~2000A short circuit (quite long cables so i dont expect it would be much more but still quite a bang if you have the plug in your hand)

When you plug the first plug in what will be on the pins of the other plug? Are you just trusting that someone won't unplug one of your plugs as you are plugged into 2 sockets (marinas only allow for one each!) if they touch the pins of your second lead and get electrocuted what would be your explanation?

You will find a lot of marinas will fuse the sockets at 10A or some French marinas even 6A so you might just need to use less power.

Also the voltage in europe is 230Vac not 240v it never has been 240v in europe! at least google the info..

[noelex 77]

Originally Posted by paul2884

Also the voltage in europe is 230Vac not 240v it never has been 240v in europe! at least google the info..

Historically, the nominal voltage in mainland Europe was 220V, and in the UK, it was 240V. In an attempt to standardise the voltage 230V was chosen as the new nominal figure, but this was mostly achieved by providing a generous permitted variation rather than any practical change.

Thus, the new standard in both Europe and the UK became 230V, but with a variation of voltages as low as 207V and as high as 253V was considered acceptable to be regarded as a 230V supply.

Thus, not much really changed, and in the UK, where the OP indicated he was posting from, the actual measured voltage is often around 240V as the equipment was designed to produce this voltage.

[m0ggy]

My experience in joining two 13a outlets into one is that it will blow the earth leakage protectors instantly in the UK. Not advised.