Does reverse polarity damage applicances?

Discussion in 'Motorhome Chat' started by jacken, Nov 3, 2008.

  1. jacken

    jacken Read Only Funster

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    Having read all the good advice here on the subject, could some-one confirm or other-wise, if the above will kill my fridge, boiler or circuit boards etc. I have a left hooker and my wiring is all continental.

    many thanks.

    ken
     
  2. scotjimland

    scotjimland Funster Life Member

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    Hi Ken

    I presume you are talking about the electric hook up ?

    Reverse polarity won't damage any appliance or components.
     
    Last edited: Nov 3, 2008
  3. Braunston

    Braunston Read Only Funster

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    Hi,

    It could however undermine any thermal protection that you have on those appliances so be careful
     
  4. American Dream

    American Dream Read Only Funster

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    I guess it's always best to carry a mains polarity tester then to be on the safe side.:thumb:
     
  5. stagman

    stagman Deleted User

    Mains 240v a.c. no damage will be done if you reverse polarity,the danger is that when you switch something off you will switch the neutral and not the live,also some boilers won't work as they have reverse polarity protection .But beware if you reverse any d.c. circuits as this will blow the components and cause irreperable damage.
     
  6. jacken

    jacken Read Only Funster

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    Thanks for the replies. The reason I asked was in Spain I hooked up without checking with my reverse polarity tester (a blond moment) and after that my fridge was acting up switching to gas whilst on hook up. It seems okay now and wondered if it had damaged any-thing.

    Cheers again.

    ken
     
  7. scotjimland

    scotjimland Funster Life Member

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    Hi Ken..

    I've had this happen too, especially on aires, it's normally due to low voltage or a dip in the voltage when there is a peak load.. , for example, when everyone switches on the kettle for breakfast... won't do any damage, just annoying..
     
  8. jolly wally

    jolly wally Read Only Funster

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    You should be so lucky?:Wink:
     
  9. hogan

    hogan Read Only Funster

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    I have a hymer with continental plugs,i cannot understand why people worry about reverse polarity.All the plugs can plug into the socket anyway around,this applies in my house also.
    So if the polarity is correct going into a socket what are the chances of it being correct going into the appliance ?-
     
  10. American Dream

    American Dream Read Only Funster

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    It doesn't........

    Most stuff nowadays is double insulated (Plastic cased) anyway.

    As long as the earth is attached to the chassis of the appliance if it's 3-core cabled and of metal construction.

    Fridge/freezer/microwave/some kettles etc....
     
  11. Jaws

    Jaws Funster Life Member

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    There's a clue in the type of voltage we are talking about here :Smile:
    A C

    ALTERNATING CURRENT

    Basically in one full cycle the +ve becomes -ve and visa versa ( effectively )
    So no damage done .. But as Stagman said, you could be switching the feed and not the return
     
  12. scotjimland

    scotjimland Funster Life Member

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    There's also a clue in the type of van..... :Wink:
     
  13. dave newell lvs

    dave newell lvs Trader-Vehicle Services

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    I have seen at least one motorhome where the Truma combi heater would knock the site trip off if reverse polarity was encountered. I have no explanation for the reason why but I can verify it did it 'cos I tested it. I have also heard from others that some electronic battery chargers do not liek reversed polarity and can be damaged, again I have no explanation for it.

    D.
     
  14. vaughan

    vaughan Read Only Funster

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    The voltage in spain, especially in winter, is notoriously unreliable. I know MHomers who have used up nearly all their UK gas cylinders when their modern fridges auto switch over to gas when the voltage drops. Best to set your energy supply to the fridge manually.
    Vaughan
     
  15. Phil

    Phil Read Only Funster

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    If I inadvertently connected to a reverse polarity supply it would trip my on board battery charger.

    I always check now and use a 1 metre long cable with one end having live and neutral reversed, ( clearly marked 'Reverse Polarity' ), in between my hook up cable and the van inlet and have had no more problems.

    I use a Maplin Socket Tester to check the supply each time I connect up.

    It should be noted that, especially in France, it is quite common to find 'correct' and 'incorrect' outputs from the same distribution point.

    Phil.
     
  16. andyman

    andyman Read Only Funster

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    Anyome have an idea why when I use my generator, the reverse polarity light on the sargent controler comes on. And is still on when i use my reverse polarity cable.
     
  17. scotjimland

    scotjimland Funster Life Member

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    I may be wrong, but I believe it's because the genny isn't earthed to the motorhome.. or indeed earth, if an earth is run to ground at the genny it should prevent this happening..
     
    Last edited: Nov 4, 2008
  18. Jim

    Jim Ringleader

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    On a trip to Spain this year most of the sites that we stopped on had reversed polarity, I do have a plug in my kit with the wires reversed for such events, but most of the time I just turn the plug upside down and reconnect it, this works a treat.
     
  19. Pikey Pete

    Pikey Pete Read Only Funster

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    Just a word of caution when you turn the plug upside down, as from time to time you may come across the system where the Earth is carried through a spring loaded third pin, so plugging in upside down will result in no Earth contact.

    Pete
     
  20. stagman

    stagman Deleted User

    That is the danger of reverse polarity.Was it the main Rcd that was tripping if so it could be that a lot of the PCBs are terminated at the same potential as the neutral or earth.Difficult to explain properly but what happens is your live is picked up as an earth fault.In your home if you are supplied by what they call a PME system ,take a look at the incoming cable by your meter and you may find your earth is connected to your neutral,please note not on all systems some have earth rods.
     
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