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Random RCD Tripping

Discussion in 'Electrics UK' started by Seb101, 29 May 2019.

  1. Seb101

    Seb101

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    Hello folks,

    About a month ago, unrelated to any changes to the system or any new appliances in the house the consumer unit RCD (that covers the ring-mains, cooker and shower) tripped randomly while we were watching TV.

    It then happened again later that week and once again just now (3 weeks later). Always seems to be in the evenings, but not at a regular time (first time it was around 5:30pm, second time was around 7pm, 3rd time was just now, 9:45pm).

    It resets just fine each time.

    Three times is enough to make me think there is something wrong. How do you go about diagnosing something like this?

    Cheers.
     
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  3. JohnW2

    JohnW2

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    Was the cooker (or shower) being used at the time. What things are plugged infto the 'ring main' concernbed, and were any of them running/working at the time?

    Kind Regards, John
     
  4. donrkebab

    donrkebab

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    An electrician can test the tripping current of the RCD.
     
  5. Seb101

    Seb101

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    The ovens were switched on (standby) but not cooking. Same with the shower, on but not running.

    I mean, there's a lot of stuff running on the ring main... fridge/freezer, tv, skybox, soundbar, modem, router, 3 lamps, couple of computers, couple of mobile phone chargers, printer, 3 amazon echos, pair of speakers.

    Nothing high-current or anything that would be 'switching' during that time.

    Not sure where to start.
     
  6. Seb101

    Seb101

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    Sure - but other than me forking out £50, what's that going to prove? Do RCDs 'degrade' over time? It's been fine for the last 5 years.
     
  7. EFLImpudence

    EFLImpudence

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    Well, it's going to prove the RCD is satisfactory - they usually 'degrade' by not working at all - and he can measure the earth leakage current on the circuit(s); it's the only way to find out.

    If it is ok, then obviously it will be something else intermittent (a bugger to find).

    The fridge/freezer may be leaking moisture on to the wiring. You could try first by plugging it into an extension lead from a socket not on that RCD.
    Is there an outside socket that might be getting wet?
     
  8. JohnW2

    JohnW2

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    In addition to what EFLI has said about condensation, fridges and freezers do 'switch' on and off whilst running - which is probably another reason to try to rule that out as a possible cause.

    Kind Regards, John
     
  9. donrkebab

    donrkebab

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    As a start try manually tripping the RCD a dozen times or more, this is called "exercising" and could loosen things up that have been sitting there doing nothing for 5 years.
     
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  11. JohnW2

    JohnW2

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    That is sometimes appropriate, but it addresses a problem which is the opposite of what the OP is experiencing.
     
  12. crystal ball

    crystal ball

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    First place I would look is the shower and associated switches, seen many a burnt out connection causing trips
     
  13. JohnW2

    JohnW2

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    Nope, any more than you are (or anyone else is).

    However, what I do know is that the last thing one needs to do with an RCD which is tripping unexpectedly is to "loosen it up" - that is something one can try if an RCD appears to be 'sticking' and does not trip when it should.
     
  14. EFLImpudence

    EFLImpudence

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    Yes, exactly.

    An RCD suspected of tripping too easily hardly needs to be 'exercised' to make it trip more easily.
     
    Last edited: 30 May 2019
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  15. EFLImpudence

    EFLImpudence

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    No, we want some valid answers.

    Did you not know that is the purpose of questions?
     
  16. EFLImpudence

    EFLImpudence

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    I was asking, not demanding. I am eager to learn from your vast experience.

    Everyone else who thinks you are giving wrong information to posters.

    Don't do it then.


    We shall conclude that you don't know.
     
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  17. donrkebab

    donrkebab

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