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Live/Earth Reverse Fault

Discussion in 'Electrics UK' started by curium, 1 Feb 2014.

  1. curium

    curium

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    Our washing machine recently stopped working. I replaced the fuse in the fused-switch but still no action.

    I pulled the machine out and stuck a socket tester (Fluke SM200) in the socket and it reported a Live/Earth Reverse fault.

    I had a look behind the socket the machine is plugged into and it all looks fine.

    I then unscrewed the fused-switch socket and the neutral-out pole looks like it has seen some action.

    I've attached pictures



    So as I understand it the Live/Earth reverse fault would be consistant with the neutral wire not being connected, so that explains the tester error.

    What is the likely cause of the damage to the neutral pole on the fused-switch socket?

    I could head down to BandQ to grab a replacement but I'd rather find out what caused this fault in case it just repeats with the new switch.

    This episode has also prompted me to consider getting an electrical inspection. How much is a test and report of my circuits likely to cost? It's a 2-bed end of terrace house with 2 rings for sockets and a ring for the cooker, 2 rings for the lighting and 1 for the smoke detectors.

    Thanks for any help.
     
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  3. westie101

    westie101

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    Poor connection causing load related (when the washing machine is heating water)overheating of the terminal
     
  4. PrenticeBoyofDerry

    PrenticeBoyofDerry

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    If the neutral out conductor is loose/broken or poor contact at the terminal, when on load you can get arching and heat at the terminal.
     
  5. winston1

    winston1

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    If the washing plugs into as socket as you say you don't need a fused connection unit as well. So don't replace it with another, replace it with a suitable 40A switch. And make sure the terminals are tight.
     
  6. EFLImpudence

    EFLImpudence

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    20A switch.
     
  7. PrenticeBoyofDerry

    PrenticeBoyofDerry

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    Fused spur off a ring final maybe!
     
  8. EFLImpudence

    EFLImpudence

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    No one seems to have commented on this but it is far more important.

    Switch off and check immediately.


    These testers cannot distinguish between Neutral and Earth so, although unlikely, all three could be in the wrong place.

    Unless the plug is similarly connected I am sure you would have noticed.
     
  9. curium

    curium

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    When the washing machine is in place the socket is not accessible. I think that's why the fused-switch is in place. Is this not normal practice?

    The socket the machine plugs into appears to be wired correctly. I'm confused as to why the circuit was broken because when I removed the fused-switch, all the wires were in place and the neutral out cable (leading to the socket) was very well connected to its terminal and needed a bit of force to remove it so while there is evidence of overheating, the circuit looks to be complete yet the machine had no power and the socket tester reported a Live/Earth reverse fault.

    I've ordered a replacement fused-switch and will try and connect it all again when it arrives. Currently I have used some 30A rated choc-blocs to connect the wires for the ring and taped up the wires for the spur socket with insulation tape and covered the whole lot with a blanking plate. The washing machine is plugged into another socket by means of an extension cable.

    Any comments on the cost of an inspection?

    Cheers!
     
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  11. winston1

    winston1

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    As I said, and you have chosen to ignore, you don't need a fused connection unit. You need a 20A switch. The washing machine plug has a fuse so you don't need another. The fact the socket is not accessible does not matter. You can isolate with the switch you have not ordered. Normal practice, well for some but it is wrong to have 2 similar fuses in series, so go and order that 20A switch.
     
  12. PrenticeBoyofDerry

    PrenticeBoyofDerry

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    What seems to have been ignored is the set up of the circuit, maybe it has to be a fused connection unit as there are more than one socket protected by the FCU. If that is the case putting an isolator in place of a FCU would not comply to the requirements of a RFC.
     
  13. winston1

    winston1

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    Unlikely I think is it is supplying a washing machine.
     
  14. PrenticeBoyofDerry

    PrenticeBoyofDerry

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    Unlikely, so would you be happy to install/amend on an assumption of unlikely or would you consider the best option would be to investigate further and confirm?
    I have come across installs where a FCU has been protecting a Washer socket, a dryer socket, a macerator, then on to socket where a kettle was plugged in.
     
  15. RF Lighting

    RF Lighting

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    Just use an FCU as was there it the first place and they you know for sure you're good to go.
     
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  16. PrenticeBoyofDerry

    PrenticeBoyofDerry

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    Exactly my point!
     
  17. winston1

    winston1

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    My point was if it was wrong initially, now is the time to put it right.
     
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