Reverse Polarity is nothing to do with your compass pointing in the wrong direction! It is something that can happen when you plug into the Electrical Hook Up (EHU) on a caravan site. It is unusual for it to happen in the UK, it is more likely to happen when touring on the continent. So what is it and how does it affect you?
Reverse polarity is quite easy to understand and once you know about it, it’s fairly easy to correct. Simply, it is the live and neutral wires are the wrong way round on the EHU bollard.
“Wow… that was some mistake by the electrician that wired it up wasn’t it?” Well, not quite. To understand how the situation comes about we need to go back in history a bit. When electricity was first started to be distributed and sold on a commercial-scale, all the switches had two poles… a live and a neutral, so when you switched something on, both live and neutral were connected at the same time. Conversely, when you switched something off, both live and neutral were disconnected. Quite simple really and quite safe. So we and the rest of Europe carried on switching both wires. At some point, some bright spark (excuse the pun) said… “Hey, we can save some money here on switches. Lets make them so they only have to switch the live on and off… leave the neutral connected” To make sure we got it right, we coloured our wires Red and Black so everyone knew which was live and which was neutral. Meanwhile in Europe… they said “…Pfft….” and carried on using ‘two pole” switches and their cables stayed black and grey or white and grey or black and white.
We became obsessed slightly and said “what if someone wires it wrong?… we better put another cable in there” so we suddenly gained an ‘earth” cable… coloured green for our protection. The electricians in Europe liked the idea of an earth cable so they had a yellow one… or green depending in which country you were in. Now, the cable manufacturers were up in arms… “can we please agree on a colour for this earth“… no agreement was made, so the manufacturers got smart and made the earth cable stripey… green and yellow stripey to be exact. We saw the new stripey cable and thought “this is good” so we went stripey too, and not to be out done we decided that Brown was the new Red and Blue was the new Black!
Now I may have just re-written history slightly there… but I think you can grasp what went on. So here we are… Brown, Blue and Green & Yellow cables and switches that only operate on the live (Brown) cable, While our continental cousins still use White and Grey and Black… with a Green & Yellow striped earth but importantly switch both the live and the neutral.
So what goes on when you plug your caravan into a bollard?. Well, the current flows down the brown wire to your circuit breaker, then on to your socket and in to your appliance… lets say a toaster. It returns up the Blue wire and back to the EHU bollard. When you switch off your toaster, it turns off the Brown wire and stops the current flowing. If you turn it off at the socket on the wall, it still stops the current flowing down the Brown wire. If you turn it off by flipping the little switch on the circuit breaker, it still stops the current flowing down the brown wire to all the sockets.
Now, if we plug into a continental bollard, that has the live and neutral the wrong way round and we look again at our toaster we see there is a problem. We turn the toaster off and this time the switch is on the neutral or return path, so when we switch it off, the element ‘may’ still have a voltage present on it. If we turn it off at the wall socket, again we switch off the neutral side of the circuit, so the toaster still might have 240 volts going to it. Even if we switch it off at the circuit breaker… it will still might have 240 volts going to it.
Now 99% of the time, this is not a problem…. until that is, someone decides to put their fingers into the toaster for what ever reason…. they can touch a live element. So the toaster doesn’t even need to have a fault with it. It can still be potentially dangerous.
Keep Calm and Carry On
Don’t get too panicky though! Modern caravans are fitted with and RCD (Residual Current Device)… It’s the job of this little device to check the current flowing in on one wire and out on the other. If it detects that more current is flowing in than out because it’s leaking out somewhere – it switches off. The RCD doesn’t really care what colour the wire is that the current flows in and out on, it just wants to see the same on each wire.
Martindale CP201 250V Industrial Check Plug
Now how can we correct it? Well, checking for reversed polarity is easy and simple. All you need is to buy a “socket tester”. You can get them from various outlets, I have listed a few links at the bottom of the page. They are simple to use and will usually have three lights on the front. Just look at the lights that are lit and they will have a label on the front telling you what each light means. If it indicates anything that is not “normal”, switch off your van’s master switch and unplug from the bollard. If necessary, consult the site warden before you do anything else. I prefer to use a Martindale CP201 tester, so I can check the bollard before plugging my van in. If on the continent and you use one of the continental adaptor leads, you can check that before you plug your van in. I’ll assume though you are using one that plugs into the normal 13 amp household socket in your van.
Now, if it indicates reverse polarity, you must switch off and unplug from the bollard. Now we can correct a reverse polarity bollard. The best way is to have a short lead, like your 16 Amp EHU lead with the blue plug and socket. This one only needs to be about a foot (30cm) long. The plug is wired up in the correct way… brown to live, blue to neutral and green/yellow to earth. The socket at the other end however needs wiring up the wrong way… Brown to Neutral, Blue to Live and Green/Yellow to Earth. If you are unsure about this, please go to your local qualified electrician, they will be able to make it for you for a small charge. It’s better to pay to have it done correctly than attempt it yourself and get it wrong. It is vitally important that you mark the lead “Reverse Polarity Correction Lead” clearly and make sure it stands out.
A note of caution. There are some of these leads available via on-line sellers at a well-known trading site. The ones I have seen are made with 1.5mm cable and are not really safe to use at 16 Amps. They won’t catch fire or melt, but they might warm up a bit at the full 16 amps. Any EHU lead that is supplied with a new caravan must be made of 2.5mm cable. I don’t see any reason reverse polarity leads are any different. It is actually illegal to sell these “reverse polarity correction leads” in the UK. It is however, not illegal to make one for your own use.
If you are unsure about any aspect of reverse polarity and using a “reverse polarity correction lead” Ask a qualified electrician. If you have any doubts about your ability to make one… don’t… get your local qualified electrician to make it.
Testers can be bought from these and other places: Maplin | Amazon | PASS |
Post updated June 2012Copyright © 2011 – 2020 Simon P Barlow – All rights reserved
Caravan Chronicles 
I have a fiat decato 2022 model
When I go to the UK and plug in to my daughters house electric after 2 days it seems to drain the drive battery (engine battery) could this be because it is a foreign camper and is getting reverse polarity from her house.
Kind regards Mr Shinn
Hi
The engine start battery is not connected to the habitation electrics, so even if there was reverse polarity it could not drain your engine start battery. There may be a 12 volt engine battery maintainer plugged in to the 240 volt AC habitation electrical system, but this would still work even with reversed polarity.
Thanks for your reply.
Can’t understand why it doesn’t go flat on french electric supply but only when plugged into English.
That was the only possible cause we could think of .
Is there anything else that could cause it
Kind regards Mr Shinn.
The electrical supply is virtually identical in the UK as the supply in most of Europe, 220 to 240 volts AC. The only difference is the connection plugs. In the UK either the blue 16 amp (found on campsites) or domestic 13 amp. If you are getting power into your van, and everything is working as it would in France, then I would look at other things. The temprature in the UK is usually cooler which has an effect on older batteries and they self discharge quicker. It might be worth getting the engine battery tested. An alternative maybe installing a small battery maintainer/charger for the engine battery when you are hooked up to an electrical supply.
Thanks Simon
Have got a charge maintainer on but the drain is so much the charger can’t maintain it when plugged into electric in the UK if we un plug electric then drive battery is fine it only happens when connected to power in UK .
There must be something else going on then. Connecting to a UK supply should be no different from connecting to a French (or other European) supply. If the electrical sockets in the van are working as they would when connected in France, then everything should be the same.
If the power draw from the engine battery is that great a battery maintainer isn’t keeping up, then something must be drawing current from the battery. Is there anything in the van left on when the ignition is turned off?….. GPS, Radio, WiFi access point, phone charger…. or anything plugged pin to a 12 volt socket you don’t normally use in France?
Thanks Simon .
No we check this every time three times we have been to England and it has done it every time.
When we left it on on over night at one daughters it flattens in 2 days.
At my other daughter we nly had it on for a few hours so we assumed there was a problem at my first daughters but this time we left it on all night at both and it did it at both so it only happens in the UK on hook up .back in France I plug it in with everything on as if we were using it leave it for days no issues at all .
Have had engine battery checked and is fine .fiat says it to do with the camper Side not interested and the camper dealers say as it’s the engine battery it’s down to Fiat so no help there.
Kind regards Mr Shinn
Well unless there is something odd with the adaptor you use to go from UK to Continental connectors then I’m at a loss to be able to explain it.
Its really got me thinking this problem.
What changes between being connected in France and plugged in here in the UK? I assume you use the same shore power cable to connect the van to the supply in both France and the UK. So that cannot be the problem. The only difference then is the adaptor to connect from a UK socket to your shore power cable. If it was reversed everything would still work, if it was an earth – neutral cross, it would trip the electrics of your daughters house. If it was a live – earth cross it would trip the electrics in the house.
So as far as the van is concerned it is getting electricity down the same cable in France and in the UK. So what is different and why should your start battery drain in the UK but not in France? The start battery doesn’t discharge if you are not connected…. so why in the UK would that happen….. ?
OK…. here is something that would need to be looked at….. you said you park it up at home and plug it in and everything is OK the battery stays charged…. yet here it flattens. I wonder if staying in the van is the problem…. there might be some 12 volt circuit that you use when staying in the van that is connected to the starter battery and should be connected to the leisure (house) battery… lights, water pump, toilet… try disconnecting the electrical supply AND the house battery and see if any circuit still works…. interior lights, water pump, fridge, toilet flush.
Im starting to think that maybe there is something or a circuit connected to the engine battery rather than the motorhome house battery.
Thanks Simon.
Have tried that and everything stays on no spark from battery when taking it on and of so doesn’t seem to be any type of draw am going to plug the electric in then pull battery see if there is a spark .there is no alarm or mobilizers on van either so noz draIn from them .
Hi Simon. We’re in Spain on a relatively new campsite and are having problems with one of our our leisure batteries overheating. We have a 2018 uk purchased Pilote Aclass Motorhome. Could this simply be due to the site EHU having reversed polarity (not checked it’s yet) . It’s a typical European 2 pin connector on the EHU to the standard mains lead adapter.
If so can I overcome this by simply turning the plugin connector “upside down”. Therefore basically swapping over the connecting left and right pins?
Fantastic article by the way, very informative and interesting.
Thanks.
Hi Dave
The reverse polarity problem is not really too much of a problem and I would not worry about it too much and it won’t have anything to do with your battery issue.
The battery however is another thing. You say ‘one’ of the leisure batteries overheating. I’ll assume that there is a bank of two. Batteries overheating mean that there is either something wrong with the battery OR something wrong with the charger and it’s over charging.
As you say ‘one’ battery is overheating, (I’m assuming the other battery is OK therefore concluding that the charger is OK too) then I tend to suspect that you have a cell down in that battery and it’s causing the problem. You need to disconnect that battery and remove it. Overheating batteries “out gas” a lot which is not good and potentially dangerous.
I would lean on the side of caution and plan on replacing both batteries. One has gone down, the other may not be in good health either.
Great article Simon. Thanks.
I have one query that doesn’t get mentioned though – AC.
The mains supply is obviously an alternating current, so doesn’t really feed in through live and out throught netral, because they’re alternating 50 times a second.
So I’m confused about what the actual difference between live and neutral in this scenario, and why reversed polarity matters.
Hi Russ
Easy one really…. in domestic AC supply the neutral and earth are linked together back at the local transformer or generator, therefore earth is really the same as neutral. However we limit all current return from the live side of things to the neutral wire leaving the earth wire ‘free’. This means we can install devices that detect any stray currents crossing to earth and switch the supply off. (ELCB’s Earth Leakage Circuit Breakers) Now when everything is wired correctly this all works fine. However in the UK we only install single pole Circuit Breakers on the live wire, so an overload/short/fault will trip this and everything is safe. However if we plug our motorhome into a reverse polarity supply, the Circuit Breaker is now on the neutral side. An overload/short/fault will still trip this circuit breaker…. BUT then neutral wire is the live wire with respect to ground, all that has happened is we have ‘switched off’ the live wire acting as neutral. There is still a live voltage on the neutral wire.
OK, if something trips you generally start looking into why. However In the UK we only install single pole switches in wall sockets and electrical devices. SO you switch something off at the wall socket, but the neutral wire is still live (with reversed polarity) so the toaster that you think is switched off at the wall is still live, and as we only switch the live side of things in devices… you put your damp hand in to pick it up and move it…. the elements are connected to the neutral…. which is actually live and……
On the continent circuit breakers generally are two pole and they switch off both live and neutral, so it’s not that important which way round they are.
Even in AC circuits you have a designated LIVE and NUTRAL as it is always with respect to EARTH.
Neutral is always (there are exceptions) linked to Earth at the generator, transformers on the transmission cables and often when you see 2 overhead wires going across fields to a farm, the neutral will be tied in to an earth rod stuck in the ground every few poles and usually at the farm building there will be a pole mounted step down transformer with a cable connecting the neutral to a big earth rod driven into the ground at the base of the pole.
Hi, I now understand what reverse polarity means after eating your very helpful article. Could you please tell me if hooking up a leisure battery in a Uk campervan to a reverse polarity cable would a) work to charge the battery and/or b) cause any damage to the battery? We’re having weird electrical problems and trying to narrow down the cause. Many thanks
That should of course say ‘reading’ your article!
Hi Andy
I’lll make the assumption you mean hooking up a mains lead to a EHU bollard. Hooking up and using a reverse polarity lead or hooking up to a reversed polarity bollard socket won’t have any affect on your leisure battery. The battery will continue to charge and work as normal.
Thank you so much for the quick reply. Glad to know we haven’t done any damage.
I have bought Hymer & Dethleffs caravans in the UK and the circuit breaker was changed to uk standard making it unsafe on the continent.
The dealer said it had to be changed to be sold in the uk. Is that correct?
Surely a two pole breaker would meet uk requirements and more.
Jim
Hi Jim
Legally, if any caravan is sold in the UK it has to conform to UK regulations…. technically, well lets say plenty of Europeans bring their caravans and motorhomes to the UK and they are OK. Likewise, plenty of UK caravans and motorhomes travel to Europe and they seem to be OK. At least I’ve not heard of any issues.
I do know of a couple of people that have bought their caravans in Europe and used them there for a while then brought them back to the UK and they haven’t done anything… including leaving the continental sockets and just use plug in travel adaptors.
it’s all a bit mute actually as a lot of the regulations some consider not to apply as the caravan as a whole is classed as an ‘appliance’ as it can be plugged in and unplugged… just like a kettle.
In my personal opinion, if it is safe to be sold in Germany (or any other EU country) and plugged in anywhere in Europe… then it should be safe here.
If the UK regulations imply that foreign wired caravans are not safe here then there would be a ban on foreign travellers plugging in to our camp sites.
I agree completely.
I thought it was ridiculous that when I went to Europe with a German caravan to consider reverse polarity.
I have seen many checking polarity after decades of European travel, now that most appliances are double insulated the risk is reduced but still there.
I did consider buying in Europe and bringing the caravan back to the uk not just for the electric issue but they were 20% + cheaper at the time. Some of that money paid for conversion I did not need.
Jim
I’m currently in a site in Poland and my docket tester is showing no earth.
Will this be an issue if I leave it connected to the hookup?
My van has an rcd wired in
Hi Phil
This is not uncommon in eastern Europe where supplies and wiring tend to be a bit ‘different’.
As you have an RCD if you get a short or overload fault you will be protected by the MCB’s (Miniature Circuit Breaker) as this looks at the current coming in and as long as it doesn’t exceed the MCB’s rating your OK.
The RCD works by balancing the current coming in on the live and going out on the neutral as long as they are the same it stays on. If there is a difference however (i’e some current leaking down a path to earth) it turns off. The issue is you don’t have an earth path for this to work properly so it may not work in all cases.
Don’t despair however, most electrical appliances are double insulated (the symbol is a square within a square) so should be OK to use. Caution should be used though with things like toasters, kettles, microwaves that are not double insulated and relay on an earth.
Personally I’d unplug the microwave (as it has a metal case normally bonded to earth) and not use it. The same goes for the electric water heater, turn it off at the breaker if you can and use gas… and be careful using a kettle or toaster.
If you think about it though, how many sites have you been on with an earth and you didn’t have any faults that tripped off the RCD.
Thank you Simon. I haven’t had any issues with ‘shorting’ or ‘trip switches’ at all in the last 4 weeks across Europe.
The kettle and microwave outer casing is plastic.
I’ll keep an eye on it and unplug the hook up before we go to bed.
I still have leisure batteries anyway.
It’s a shame because this site is very new.
Thanks for your help
Hi Phil
If it is a new site, it might be worth having a word with the staff as they may not be aware of the problem… or if you can see if you can test another hookup point it might just be the point you are on.
Hi. This makes interesting reading and I think I will need to make up one of those leads.
I was plugged into a French camp site.
My Zig unit has been over heating, I was putting it to the intense sun and heat! (Maybe it still is that)..
However I had a DVD player plugged in and suddenly it switched off, so I thought. I believe it was too low power and was just clicking.
The unit would not come on with the mains switched off and the charge off. Usually I get it switching back to leisure supply.
So I had a thought, after checking all fuses and under the bonnet, unplugged from the site post and switched to charge from main engine battery. Turned the engine over, ‘hey presto’
My question….
I take it that the reverse polarity is the problem, and could be overcome with a new ‘reverse polarity’ lead?
Thanks
Mike
Hi Michael
ZIG units do have a bit of a checkered history and running warm is one thing I think from memory.
The other thing to keep in mind in France is in some rural areas the electricity distribution is a little sketchy voltage wise and it’s not unknown for a large -(by UK standards) voltage drop. This is basically down to the French distribution system has a large area to cover and in rural areas transmission lines are running at capacity… especially in warm weather when lots of air-con units are running. So your ZIG running hot might be down to the local voltage dropping down to 180 lots or something similar.
One handy bit of kit to consider is one of those plug in energy monitors. Most have a voltage readout setting so you can simply plug it in and measure the voltage at one of your caravans sockets.
Hi Simon
Had a response come through from the NIC at last:-
Rob,
Thank you for your enquiry.
Unfortunately this question is outside of the scope of this service and therefore we are unable to give you a specific answer.
We can only suggest referring to manufacturers instruction or speaking to them direct. You may also consider PAT testing the modified product.
Regards
NICEIC & ELECSA| Technical Services
PAT Testing will just result in reverse polarity fault lol.
Cheers
Rob
Hi Simon
I have just sent another email and will let you know the outcome.
Thanks
Hi Simon
Thanks for your input, as you mentioned before I too have seen some bad home made adapter leads which is why I come up with the idea of selling them. I’m sure my last email from the NIC just said the regs are for guidance and not law, so they couldn’t definitively answer yes or no. Its been a struggle to get any sort of clarification on this. I will try again with the NIC and maybe get someone a bit more helpful.
Thanks for your time and a great post.
Hi Bob
If you do get a definitive answer, can you let me know as I would like to post an update clarifying the situation.
Cheers
S
Hi Simon
Thanks for your quick reply, I’m an electrician and very interested in making and selling these leads, although all my leads will have the 2 pin eu plugs on so can only be used in Europe. I can see the 16A blue commando cross over lead could be dangerous as you could accidentally use this in the UK. I have tried contacting the NIC and the British Standards but no one will tell me if its Illegal or not to make and sell.
Do you know who to contact or how I could get these leads made within the UK law, as I’m a bit stuck now.
HI Rob
The NICEIC or IEEE would be my first thoughts of bodies that might have some guidance on this.
I’m not 100% sure, it is my interpretation and understanding of the regs from when I did my 17th edition many years ago.
Personally I made one using the blue commando fittings so I could connect it and lock it in the compartment where you connect into the caravan to ensure it was not unplugged/removed by anyone rather than connect it at the EHU bollard.
If you are making them with the 2 pin euro on one end.. like you say would be used outside of the UK… however the issue could be down to product liability.
I have tried to plug in my electric in my camper however keep having red light saying negative polarity how can I reverse this
Hi Carole
If it has happened only on one site, then logically your camper is OK but the site connection may be wired incorrectly. However if it has happens on every site you try to plug into then logically your camper has incorrect wiring.
If it’s the former, it is easy to create a “reverse polarity” lead and any electrician could make up a short lead to do this.
However, if it is the latter, you need to get a qualified electrician to check things out on your camper.
CAUTION: You can buy reverse polarity leads on a well known auction site, however in the UK to actually sell these is illegal… but it’s not illegal to make your own.
Hi Simon, Just interested to know why these are illegal to sell in the UK when you can only use them in Europe.
Hi Rob
As I understand it, you cannot manufacture and/or sell any electrical items that don’t conform to current safety regulations or current UK wiring Reg’s. Therefore this renders them illegal to make and/or sell.
I have also seen one that was sold on a well known auction site that only used 2 core cable, the earth had been omitted! (I think they had used the two core 1.5mm2 orange cable designed for double insulated lawn mower/hedge trimmer use)
However within those same regulations there is nothing to prohibit their use or an individual making one for their own personal use.
GOLDEN!
Cheers, Simon.
A few people say that some sites in Spain are not correctly earthed, or don’t have an earth. I don’t know if this is true or not. So what happens then if the supply doesn’t have an earth?
If there’s a fault an rcd will trip even without an earth wire back to the bollard, if there is another route to earth, but if a motorhome or caravan isn’t grounded, because of the insulating tyres, and/or steadies on plastic blocks, then if you touch a “live” appliance or piece of van metalwork that’s live then you’ll become live too, but no harm will be done unless you touch ground and become earthed, in which case the red should trip. But not a very satisfactory state of affairs.
Hi
Most modern caravans and motorhomes are protected by RCD’s. RCD’s work, by detecting the current being supplied on the live feed and comparing it to the current leaving on the neutral cable. If you touch a live component and earth it, there will be a slight imbalance between the current on the live side and the current on the neutral side (some of it is leaking through you to earth) then the RCD will switch off. So in reality you don’t actually need an earth cable as long as the supply to your caravan or motorhome is earth bonded at the substation to provide an earth return path. By having an earth to your caravan or motorhome gives you an extra level of protection.
All that said, I do check for a functional earth with my plug in tester each time we hook up to a bollard and I would always think carefully about whether I really needed power using an un-earthed supply, and I’d always report it as sometimes the site might not be aware of it.
I think the standard figures for RCD’s are around 10 mA difference in current between the two conductors and a trip time of 60 mS – but don’t quote me on this I’m doing it from memory.
We’re about to take delivery of a Challenger motorhome here in Spain, do I have to worry about reverse polarity when using our motorhome in the UK or Europe?
Hi Glenn
Honestly I don’t actually worry too much about reverse polarity. The UK wiring standard only requires switching on the live circuit at sockets, where as in Europe they switch both live and neutral. As long as you understand this, then reverse polarity becomes less of a worry. As the motorhome is protected by a ELCB that will switch off both live and neutral in the event of an earth fault you are protected. The owners of continental motorhomes and caravans don’t seem to consider reverse polarity as an issue. For piece of mind, it is fairly easy to make up a reverse polarity lead.
S
hi
we will be using our motorhome for 10 nights off grid and planned to hook into a friends new Honda generator that they power their caravan with but when we tried it using our normal hook up lead our control panel said “mains polarity reversed” any ideas? daren’t use it now.
Hi Carol
Generators don’t have the earth tied to the neutral line, as it is in your home or on a caravan site EHU, this has the effect of causing the reversed polarity light to sometimes come on on some caravans and motorhomes. If the generator is fairly new and been serviced regularly there should be no problems in using it with your motorhome.
Simon
Thanks Simon,
I can stop worrying about reversed polarity. I’ll get an ELCB fitted too.
We are planning a caravan holiday in the UK next year. Is there anything I might need? I was thinking about electrical adaptors. Do UK sites use the CEE socket on the electrical posts or the UK 13 Amp socket?
My wife was wondering if there is a site handbook avilable, either in book form or on the internet?
Lots of questions there. Thanks for the wiring diagram for 13 pin towing plugs We have just returned from a 2 week holiday touring in Southern Norway. The towing electrics worked like a dream, and there was no worry about the caravan fridge draining the car battery when the combo was parked.
Hi Andrew
The CEE 16A plug is the only socket used for caravan hook up in the UK, so you won’t need any adaptors.
To research sites, the best way would be via the two main UK clubs….
http://www.caravanclub.co.uk/
http://www.campingandcaravanningclub.co.uk/
You can find all the details about the sites and find things to do around the local areas. SOme of the sites listed in the two links require you to be a member of either club, the mains sites are open to non members. Each individual site web page will carry this info.
Glad the wiring worked out 🙂
S
Very good informative post Simon, most interesting, I would think many would not give this a thought when plugging in abroad untill now!
Kind regards
Colin
Hi Simon,
I live abroad and my caravan has 2-pin continental earthed sockets internally and an external CEE plug for the mains supply. Is reverse polarity an issue for me?
The caravan is equipped with a two pole 13 A circuit breaker. Is an earth leakage circuit breaker a desirable addition to the mains electrical system?
Hi
If your caravan is fitted with 2-pin ‘continental’ sockets and two pole circuit breakers, then it’s probably wired to European standards. Caravan’s and motorhomes manufactured in Europe are wired the same way and reverse polarity is not an issue for them as both conductors are switched, only UK manufactured caravan and motorhomes switch one conductor – live, therefore reverse polarity poses more of an issue.
An ELCB would give an additional layer of protection.
S