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  • I can’t remember if I posted about the mystery circuit in my utility room before or not. Basically a 32a spur from the CU with a single 13a switchfuse and socket on the end that kept tripping the MCB after a random amount of time (30 secs, 10 minutes, etc).
    Changed the corroded socket, still trips.
    Changed the breaker (to 16a), still trips.
    Changed the switchfuse, still trips.
    Noticed a spark when putting it all back together - wtf 240v on the earth (measured between the earth core and an earthed water pipe).
    No continuity between line and earth when the breaker is off.
    What is going on?!

  • Someone more qualified will likely be along shortly, but it sounds like the cable is damaged maybe. Can you do an insulation resistance test?

  • I’m going to borrow a megger from work tomorrow and try that, just seems odd to get a voltage with no continuity.

  • Most skirting boards confirm to one of about 8 profiles

    (Handy guide to some of them)

    The bad news is that while it is easy to find an approximate match for most skirtings it's actually very difficult to find an exact match as radiuses (radia?) Change depending on the material they're made from and the method of manufacture and if you don't have the tools to produce a specific radius it's gets very expensive very quickly (spindle moulder bits ain't cheap).

    The good news is that if you can find an approximate match most people dont notice the fact that profiles aren't exactly identical, especially if they meet at a corner.

    TLDR depends on how anal you are Vs how deep your pockets are

  • If the earth is broken somewhere its apparent voltage will free float. If there's also a high resistance fault to live its measured voltage will become that of live. Whereas continuity will only buzz if there's a low resistance between the conductors.

  • Got a pic? I’ve got a magic builder arriving tomorrow who loves answering this kind of question (while rolling his eyes and adding zeroes to the bill).

  • Makes sense, I think. Are we basically saying the cable is probably fucked somewhere in the run? I’m not sure what the size is but it’s heavy twin & earth and the main conductors only just fit into socket terminals. Chased into the wall behind tiles (which is where a popping noise comes from when the MCB trips).

  • radia?


  • which is where a popping noise comes from when the MCB trips).

    Surely this is suggesting fucked cable.
    Could disconnect fused switch and see if you have continuity between EL, EN, LN.

    With the breaker off, of course.

  • How much does it cost to move an consumer unit and the electicity meter? They are next to each other on a garage wall and only require moving under 50 cm.

  • Oh hai!
    If you could ask him/her, that would be wonderful!

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  • The meter can only be moved by the utility company. You can ask them to supply a 100A cutout on the meter tails.

    Then a sparks can then move the CU safely. The cost depends if the sparks deems the CU move mean an upgrade to an 18th Edition unit and the subsequent retest.

  • 32A on a radial will need 4mm T&E.

    You've either got a high resistance fault between L and E or hidden behind the tiles is an old socket and there is choc bloc where the L and E has been miswired or loose connections.

    Either way you'll need to get the tiles off to find it.

  • Oh. By the way when you do IR test it make sure there isn't a neon indicator on the SFO as it will give a false reading.

  • Hammers; 16oz Vs 20oz. How do I choose what to buy?

  • We had the gas meter moved in our previous flat, it was less than a meter so cost something like £160. Over a meter it was over £1k.

  • What are you using it for? What type of hammer?

  • Thanks, was planning to disconnect that fully and check both cable runs separately- the SFO is brand new so shouldn’t be the issue.

    I think your previous post probably nails it - is the pop likely to pinpoint the fault source?

  • I'd probably get this. For general DIY you're likely to have more smallish things to use it for, rather than driving in big long nails, so heaver a weighted hammer is just going to be more cumbersome and you'll seldom have the advantage of the extra power. Also easier to swing a smaller hammer well.

  • Product Features.

    Solid America Steel
    Sleek new profile make them lighter and more aerodynamic
    Genuine Leather Grip
    Made in the U.S.A.

    Sounds about right for a bicycle forum

  • Looks like the wall might have been skimmed without removing the skirting board. Does that seem possible or something you could find out with a little investigation?

  • I haz a titanium hammer. #trufax

  • Force = Mass x Acceleration so a lighter hammer isn't really much of a penalty right?

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Home DIY

Posted by Avatar for hippy @hippy