Help with power cord

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v v

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So we're bringing our European camper to the US soon and need to make a few alterations to suit US camping practicalities.

Internally we use 230v electrical power in Europe, of course power in the US is 110v. We have a number of electrical devices that are 230v including the battery charger. As many will know a common method is to use a 'Step-Up' transformer, these are used on construction sites in the UK so not completely unknown.

What we need to know is what type of plug and socket type(s) are used in US campgrounds. Do they vary, are there different types for different regions, is it the same for camping as commecial use etc etc.

But most of all what do the plug(s) and socket(s) look like? Help please.

Is it possible to post a few photos of what these look like?

We have an electrical company here who will make us a 30' lead/cord with a plug to connect into the transformer, but they need to know what is in common use in US campgrounds for the other end.

Thanks for any help
 

JudyJB

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You are going to need a 30 amp cord and plug, like this one:
25' 30-Amp Power Grip RV Extension Cord

Is your current power plug permanently attached to your rig? The item above is intended for rigs where it just plugs into a receptacle.

If you scroll down on the page above, it gives you more technical details. The point is that you will need more than just an appropriate plug because the wire has to be heavy enough to handle the amperage.
 

Alaskansnowbirds

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VV, You will find that most commercial campgrounds here will have both a 30amp 110vac receptacle and a 50amp 220vac receptacle. The electric panel will look something like this. The 30amp is three wire, one hot leg, common and ground. The 50amp is four wire, two hot legs, common and ground.

The plug (NEMA 14-50P) will look like this.

I would also suggest that you carry a meter with you so you can check the receptacle before you plug in.

If you can plug into the 50amp receptacle, you won't need your transformer. But bring the transformer because you will find campgrounds that don't have 50amp service.
 

Isaac-1

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I will say that many, perhaps most commercial RV parks in the US have a 50 amp 120/240V 4 prong NEMA 14-50R outlet, as well as a 30 amp 120V 3 prong TT-30R outlet, many will also have a standard NEMA 5-20R 120V 20 amp 3 prong household style outlet a large number, perhaps even a majority will only have a 120V TT-30 outlet, perhaps with a 5-20R 20 amp standard duplex outlet. With the majority of pubic (state parks, municipal campgrounds, COE parks, etc.) tended to only have the TT-30, 120V 30 amp outlets, and a few only having a 20 amp 120V NEMA 5-20 duplex outlet.

It is also somewhat common for commercial RV parks to charge about $5 per night more for using the 50 amp outlet vs the 30 amp outlet. This may either be done by charging higher for "50 amp" sites, or charging higher for which one you plug into. We were at an RV park last week that worked this way, all sites had both 30 and 50 amp outlets, they just charged more if you plugged into the 50 amp outlets. It should be noted here that a 30 amp 120V outlet can provide a maximum of 3,600 watts of power, where a 50 amp 120/240V outlet can provide up to 12,000 watts of power.
 

CharlesinGA

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My question to the OP is what are you going to do about the cycles? stepping voltage up or down is not that difficult, however, in the rest of the world, the current is 50 hz (cycles) while in the US it is 60 hz (cycles). The difference in cycles will cause clocks to not be accurate but also will cause motors to run hot, I doubt the power converter (battery charger) will work properly unless it states 50/60 hz on the data plate, and a microwave will also have problems.

By the way, standard voltage in the US is 120v in most places. 110v has been obsolete for many years. Everywhere I stayed on my recent trip to South Dakota was providing 120v or better. I was quite surprised actually.

This is the standard TT30P (travel trailer 30) that is used by many RV's Progressive Industries RV TT-30P

439d5a_177e2bb4213d4c6ca745045f79bc1643.png

439d5a_4f215dad17844ef6a7990e085f2fb42e.png

There are many different brands of the TT30P, however I highly recommend the Progressive Industries one because it is well made.

The cable needs to be 3 wire, 10AWG (American Wire Gauge) which is 2.59mm diameter conductor.

If using European cable, the Blue wire will be the neutral (white here, silver screw), the Brown will be the hot (Black here, black or brass screw) and the ground/earth is Yellow or Yellow/Green spiral stripe (Green here, green screw)

Charles
 

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v v

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This is a very helpfull response that I'll ask the company to take a look at if that's ok?
I understand most of what is written but not sure of why a 4 pin plug is used.

I'll have more time to read all the detail tonight and will try to post photos of the type of equipment that is used in Europe so you can see what I need to convert to.

Thank you all very much indeed.
 

NY_Dutch

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This is a very helpfull response that I'll ask the company to take a look at if that's ok?
I understand most of what is written but not sure of why a 4 pin plug is used.

I'll have more time to read all the detail tonight and will try to post photos of the type of equipment that is used in Europe so you can see what I need to convert to.

Thank you all very much indeed.
The 4 pin plug (NEMA 14-50P) is used because North American RV's use a neutral connection to provide 120 volts between the neutral and each leg of the 240 volt supply. Very few RV's actually use the available 240 volts for any appliances, but the combined 12,000 watt capacity allows using more appliances at the same time than the 3,600 watts available from a 120 volt 30 amp supply.

As mentioned the 60 versus 50 cycles could also be a concern in that it may affect clocks, microwave ovens, TV's, and other electronics. Your TV's also may not work correctly due to the difference in the European versus North American standards.
 

Ex-Calif

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My question to the OP is what are you going to do about the cycles? stepping voltage up or down is not that difficult, however, in the rest of the world, the current is 50 hz (cycles) while in the US it is 60 hz (cycles). The difference in cycles will cause clocks to not be accurate but also will cause motors to run hot, I doubt the power converter (battery charger) will work properly unless it states 50/60 hz on the data plate, and a microwave will also have problems.

This is true for motors but electronic devices (if marked ~50/60) will be fine.

When I first went overseas 40 years ago I took my US appliances. Remember the old mechanical clocks? Yeah - ran slow...

It's been a minute since manufacturers do not allow for global power supplies.

But as you point out, it's a great idea to check.
 

Mark_K5LXP

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"Most" devices that contain switched mode power supplies (nearly everything these days) are "universal" power input. 120-240VAC, 50 or 60Hz. Sometimes they'll have a mechanical switch on them for 120/240 but smaller devices you just plug in and go wherever. Specific to RV's, I have used three different converters on direct current - '0 Hz'. The power input of many supplies like this is basically a rectifier so AC or DC works the same. They boost/buck/regulate downstream from there. They're not usually spec'd for DC input but the converters, some computer power supplies and a host of other things I've tried run fine on 120V+ DC so any AC line frequency wouldn't matter.

Mark B.
Albuquerque, NM
 

Tom

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I understand most of what is written but not sure of why a 4 pin plug is used.
Be aware that the UK 230/240V is a single phase fed from a 3-phase star-conected transformer, and only needs 3 wires/pins (line, neutral and ground/earth). The US 240V is 2 phases 180 degrees apart, fed from a "split phase" supply, requiring 4 wires/pins (2 hot, neutral and ground). Hopefully, your transformer/converter company will understand and advise you accordingly.
 

Gary RV_Wizard

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Tom & Mark just explained what I was in the process of typing, so I erased my reply. You should be able to adapt US standard 50A/240v RV power to your needs, but will need both an adapter and transformer if you are in a site that offers only 30A/120v or 15A/120v.
 

Oldgator73

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We’ve lived in both Japan and England. We had 110 power in Japan with 50 cycles. Clocks lost 10 minutes every 24 hours and the microwave made a terrible bong sound. In England we were issued transformers so we could use US appliances and lamps.
 

Ex-Calif

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We’ve lived in both Japan and England. We had 110 power in Japan with 50 cycles. Clocks lost 10 minutes every 24 hours and the microwave made a terrible bong sound. In England we were issued transformers so we could use US appliances and lamps.
We had a couple of these that became useless in Japan - LOL...

1664558068374.png
 

v v

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Allier, France
Thanks again, but I'd like to explain how we are set up as this affects our power needs which are relatively small.

It's an A class but small compared to US RV's, it's 24' long. Picking up from comments above here is what we don't have:

No tv or tvs'
No microwave
We have 1 fridge freezer, the freezer is small. Runs on gas/12v/230v
No washer or dryer
No slideouts
The vacuum cleaner is 12v
No air-conditioning

When static and plugged in the battery charger and fridge are the main consumers, phones, lap tops will use either 230v or 12v

I don't think we will ever need 50A power, 30A sounds more than enough.

The power setup I imagined was this: Lead from power supply (now realise it's 120v) to transformer ~> lead from transformer to outside power-in socket ~> internally from power in socket to an onboard control box with a trip switch ~> to the various built in 230v equipment and plug sockets. Everything internally will be 230v or 12v.

Which returns us to the original question of which plug is need for the power box supply socket. It looks like the standard 3 pin plug rather than 4 pin, is that about right?

One other factor is how we will use our motorhome/camper/RV.
We have visited the US several times and have travelled through (briefly) maybe half the country, but as we are RVers in Europe and N Africa we knew if we could camp around the US with our own camper it would give us a different perspecive, and allow us to get nearer to nature. The plan is to stay 9 months in 2 visits, and to travel between 16 and 18,000 miles. We wont dwell anywhere for very long as this will be our one and only shot at doing this, therefore many of the comforts of home will be left behind, and most of them need power from one source or another.

Moving will keep our batteries topped up for some of the time, low useage is another factor for not need lots of power.

I imagine having a smaller RV/camper will allow us to access to places some larger RVs can't get to, we want to see as much as possible of the American outdoors as we can.

I'll try to find photos of the type of power connections we use in Europe, and the transformer we hope to use too.

Thank you all very much for your help and opinions, this subject is one of the more important ones we have to find a solution to, especially if it gets cold (we use a 1500w electric fan heater).
 

Tom

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Which returns us to the original question of which plug is need for the power box supply socket. It looks like the standard 3 pin plug rather than 4 pin, is that about right?
Yes, plugging into a 30amp/120volt outlet (aka receptacle) at a campground will require a 3-pin plug, like the one Charles showed.
 

CharlesinGA

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Which returns us to the original question of which plug is need for the power box supply socket. It looks like the standard 3 pin plug rather than 4 pin, is that about right?

The 30 amp RV plug I showed in post #5 will be all you need. Then a couple of dogbones to adapt other receptacles to the 30 amp.

50 male to 30 female dog bone adapter

1664572266506.png


15 male to 30 female dog bone adapter
1664572296919.png

These two adapters will allow you to be powered, (with limits) from a standard 15/20 amp household outlet which is commonly found on RV power pedestals. --or-- from a 50 amp receptacle on an RV power pedestal.

I recently camped at a state park that had pedestals with all three, and the 30 was worn out and the cord would not stay plugged in, so I got out my 50 to 30 dogbone and plugged it into the 50 amp receptacle, probably rarely used considering the short length of the site, and then plugged my shore cord into the dogbone.

Charles
 

v v

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Allier, France
This is a good example of the plug and socket that is common for camping in Europe. The wire is smaller than what we use, the most common is 3 x 2.5 mm2

With this setup the socket always has a sprung cap. This is the end that is pushed into the external power input of the camper, the cap hooks into a lip inside the box.

KAZZA'S Orange Caravan Mains Hook Up Cable Extension Lead 1.5 mm (25M) : Amazon.co.uk: Electronics & Photo

Here's a photo of the power inlet box with the cover closed. It's in front of the rear wheels and to the right of the lower fridge inlet grill.

s10364.aa.jpg
 

v v

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Allier, France
Re this

The 30 amp RV plug I showed in post #5 will be all you need. Then a couple of dogbones to adapt other receptacles to the 30 amp.

50 male to 30 female dog bone adapter

View attachment 158202


15 male to 30 female dog bone adapter
View attachment 158203

These two adapters will allow you to be powered, (with limits) from a standard 15/20 amp household outlet which is commonly found on RV power pedestals. --or-- from a 50 amp receptacle on an RV power pedestal.

I recently camped at a state park that had pedestals with all three, and the 30 was worn out and the cord would not stay plugged in, so I got out my 50 to 30 dogbone and plugged it into the 50 amp receptacle, probably rarely used considering the short length of the site, and then plugged my shore cord into the dogbone.

Charles
 

Kirk

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I don't think we will ever need 50A power, 30A sounds more than enough.
I tend to agree with you, but you do need to realize that when you step up the 120V US supply the 230V that you need the amount of current will increase nearly double. If your RV needs 10A at 230V, it will draw 20A from the pedestal at 120V.
Everything internally will be 230v or 12v.
It looks like the standard 3 pin plug rather than 4 pin, is that about right?
The key is to consider the total watts of power that you will need.
Are these plugs/sockets waterproof to any degree
They are typically protected from rain but not to standing water. What is found in must US RV parks and campgrounds will be similar to this picture.
1664576380231.png
 

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