reverse polarity

Discussion in 'Motorhome Chat' started by mojo, Dec 20, 2012.

  1. mojo

    mojo Funster

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    Just back from Spain and a campsite at Roses had a strange electrical supply.I use a crossover plug if reverse polarity shows up on the charger.This always solves the problem but not this time .Why please ? and is it safe to use if you are showing reverse polarity.
     
  2. knokinonabit

    knokinonabit Funster

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    I knew that I had read something in the handbook regarding the reverse polarity light, so I looked it up.

    What it actually says is :

    Reverse Polarity Indicator
    This light is designed to illuminate when the live and neutral mains input supply has been reversed (crossed over). If the light illuminates then there is a problem with either the site supply or the cable connecting the supply to the vehicle.

    Please note that if you choose to use your vehicle with a generator this could also illuminate the reverse polarity indicator. This is a normal side effect when using some types of generator and does not necessarily indicate a fault. Please refer to your generator handbook for further information.

    End of quote.

    So it would seem that there may be a problem with your cable, possibly.
    Have you been on ehu since you first had the light come on ?
    If you have and there was no problem then it seems likely that the problem was with the site.
    I am not certain, but if it was reversed polarity, I don't think your 230 volt electrics would work at all. Someone who knows for certain will correct me if I am wrong.

    I would suggest that running as you were could cause failure somewhere in the system.

    If you have a Sargent system you can e-mail them for advice.
    support@sargentltd.co.uk

    Hope that is of some help. :thumb:
     
  3. FM02MZO

    FM02MZO Funster

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    We had the same thing happen on one site last year in Spain, regardless of whether I used my change-over lead or my normal EHU cable the reverse polarity warning light came on, we moved on the following day and everything was bacl to normal. I can only presume that the fault lay in the site's system
     
  4. hilldweller

    hilldweller Funster Life Member

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    >> reverse polarity

    Did someone mention
    reverse polarity ?

    Oh yes, Christmas has arrived early :Laughing:
     
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  5. Wildman

    Wildman Read Only Funster

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    Alternating current flows one way for half of the cycle then reverses; so everything will work fine until there is a short in the system.
    Foreign built vans are protected on live and neutral; whilst brit vans on the live only. so a Brit van on reverse current would still have a live system from which you could get a shock if there was a fault. and that is all there is to it. Generators will generally show reverse current because there is no proper earth.
     
    Last edited: Dec 20, 2012
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  6. knokinonabit

    knokinonabit Funster

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    I knew a clever person would have the answer. :BigGrin:
     
  7. Incamania

    Incamania Funster

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    Reverse polarity!!

    Hi Mojo
    My stab at your phenoma is this.
    Some older electrical installations were not 230 volts between L and N, which we are familiar with, and which when reversed will bring on the reversed polarity light , but 110 volts between L and N ie 230 volts between 2 live phases, older installations may not even distribute the neutral wire. Generally the supply emanates from a 3 phase transformer with for example some viewed supplies connected between phases 1 and 2, some between 2 and 3 and some between 1 and 3 to balance up the phases. Depending how the reverse polarity sensor unit is manufactured and configured you could indeed get a misleading indication. We experienced similar anomalies on Norway 2 years ago.
    Hope this helps.
    ATB
    Brian:thumb:
     
  8. Wildbill

    Wildbill Funster

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    I was in a lay by abut three week ago and their was a old boy with a generator hooked up to his van.

    He was saying i never have problems with my pace maker when i am at home but when i am away with the van it always seems to act up.

    I sad to him generator not earthed can't be the generator i have had it sines before i had the pacemaker fitted.

    Earth his generator with copper sheathed metal spike pacemaker working normally.

    told him maybe he should get him shelf checked out.
    :RollEyes::RollEyes:
     
  9. pappajohn

    pappajohn Funster Life Member

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    chances are the polarity was correct but with no earth present.

    thats the reason you can get the rev light when using a generator...no earth.

    rather than rely on your onboard rev pol warning you could buy one of these gadgets...simply plug into an unused and accessible socket and leave it plugged in permanently.
    far more informative than what you have now.

    [​IMG]
     
    Last edited: Dec 20, 2012
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