Reverse Polarity

Discussion in 'Motorhome Chat' started by sylvester1954, Jul 1, 2015.

  1. sylvester1954

    sylvester1954 Funster

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    Problem with electric hook up in France. Sometimes when l hook up in a site or Aire in France l end up with the power box in my Accent showing a red light for reverse polarity so no electric. The next night on say another site it works ok but then may fail on another site visit a day or two later. In one of mymany handbooks namely Go Motorhoming (Vicarious Books) they suggest that Reverse polarity is common in France'.....and that 'Reverse polarity will not damage your motorhome electrical systems, appliances etc'. How does that comment sit with fellow and knowledgeable motorhome owners on this site please?
     
  2. mjltigger

    mjltigger Funster

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    i would suggest that most devices will be unaffected by reverse polarity however some may be damaged and I believe there is an issue around fusing of devices in that the fuse may be the wrong 'end'

    that of course is completely irrelevant if the control unit for your elevtrics turns off the power when it detects a reverse polarity... you can buy or heath robinson up a cross wired adaptor for your electric cable if you need it (as far as I know you simpoly take an ordinary cable and swap the +ve + -ve one end
     
  3. NickNic

    NickNic Funster Life Member

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    I suppose you can use a reverse polarity supply if you really want to but it's not really a good idea.

    All you need to do is carry a reverse polarity adapter. Make one up or buy from eBay All it is, is a very short hook up cable wired wrong - one end wired correctly, the other with L & N the wrong way round. You should probably carry a socket tester as well just to be able to double check.

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  4. GAVLAD

    GAVLAD Funster

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    I have one of the above reverse polarity adapters as well and got mine off eBay
     
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  5. andy63

    andy63 Funster

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    well covered subject on here.. a link to one of them
    http://www.motorhomefun.co.uk/forum/groups/reverse-polarity.27/group..
    if you have a reverse supply and its off a continental 2 pin plug remember its just a simple matter of reversing the plug to put it right as long as the box allows that...or carry a short lead which will do the same thing...make it up yourself or they are available at shops..
    ta andy
     
  6. GeriatricWanderer

    GeriatricWanderer Funster

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    What we call Reversed Polarity is normal wiring practice on the Continent as all their switches are double pole so both + and - are cut when switched off whereas UK switches are only single pole.
    If your MH is continental built it will be fitted with double pole switches.
    If UK built it will have single pole switch.
    Reversed Polarity is only dangerous to people if they poke around inside electrical appliances without unplugging them.
    It will not damage your MH.
    Just make sure your RCD trips when it should and forget RP.

    More important is to use a circuit tester to check for an earth but once again, as long as your RCD trips, you are safe.

    There are cables that will switch RP but, in my opinion, not worth the hassle.

    Just my opinion and I'm sure others will disagree but just ask how many people have been shocked, let alone killed, by RP - the same number as have been gassed. :)
     
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  7. davidbaldam

    davidbaldam Funster

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    Made a reverse polarity cable myself, very easy to do, have only had to use it twice but it's there if needed, I also bought a plug in checker, which I use every time I hook up, even in the UK. (y)
     
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  8. NickNic

    NickNic Funster Life Member

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  9. robrace

    robrace Funster

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    Had a problem on a site in France a couple of weeks ago.I had a shock off my tow bar!Guy next to me did a test and found not only was the socket reverse polarity but there was no earth!!I unplugged my lead and didn't use the electric.We were moving the next day anyway.The site owner said there was no problem!!Not sure what caused the shock but had no problems the rest of our holiday.
     
  10. Figaro

    Figaro Funster

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    I`m not sure that I have one in my recently acquired 2003 Hymer, I`ve not seen anything that looks like one, where would it be ?
     
  11. JeanLuc

    JeanLuc Funster

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    Your Hymer will have one. It is likely to be quite near to the 230V input socket. My trip box is in the base of the wardrobe where the Truma is located. It looks like a white rectangular box with a twin-ganged black switch near the top. It is on when in the up position. It is this switch that you normally use to switch on the 230V input once you have plugged in the EHU lead.
    Have a look in your Hymer manual for full details. By the way, this kind of trip, fitted by Hymer in 2003 does not have a test button on it.

    p.s. I don't worry about reverse polarity, but lack of a good earth on a hook-up point is definitely a reason not to use it.
     
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  12. laurieash

    laurieash Funster

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    The light will also come on if there is no earth mine did today when I plugged in using a extention , so tryed another and was ok. So looked in the plug and the earth wire had come out.
    connect it up all was well.
     
  13. Gorse Hill

    Gorse Hill Funster

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    Reverse polarity is dangerous, firstly the fuse is no longer on the phase conductor along with various other technical reason causing a shock hazard so needs to be addressed
    AC polarity isn't right just because it works
    Polarity in AC circuits doesn't matter, until it does
     
    Last edited: Jul 1, 2015
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  14. Figaro

    Figaro Funster

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    Thanks JeanLuc, another superb and prompt reply, many thanks (y)
    I`ve just been and had a look and sure enough it`s there in the same place as yours, but I`d never noticed it, or used it ! Should I be using it when connecting / disconnecting EHU ?
    PS I read your manual on repairs to Thetford cassette and decided to order a new one ! All that business of putting your hand inside and fumbling around feeling for things to unfasten prompted me to get the credit card out and keep my mits clean and ready of action elsewhere !
     
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  15. tonyidle

    tonyidle Funster

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    My 2005 B584 (RHD) definitely did not have an RCD. It had two ganged MCBs: one in the Live & one in the Neutral. I fitted a new box with RCD & two MCBs & divided the various supplies between the new RCBs. The certain way to spot an RCD is that, apart from having a test button, it must also have an earth connection.
     
  16. JeanLuc

    JeanLuc Funster

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    I stand corrected. I was referring to the twin-ganged item that is fitted by Hymer.
     
  17. Gorse Hill

    Gorse Hill Funster

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    Not all RCD's have a functional earth
     
  18. Figaro

    Figaro Funster

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    Now I'm just confused :eek::eek::eek:
     
  19. GeebeeJaybee

    GeebeeJaybee

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    I
    was too - so to be sure last night ordered a tester (tests polarity and earth) and reverse polarity adapter. Better safe than sorry.

    Jen
     
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  20. JeanLuc

    JeanLuc Funster

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    The white box to which I referred earlier is the mains cut-off trip switch. Here is the relevant reference from the handbook:

    upload_2015-7-2_9-50-9.png
     
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