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Socket trouble and no RCD?

Discussion in 'Electrics UK' started by pachmarhi, 25 Jul 2020.

  1. pachmarhi

    pachmarhi

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    We have been having trouble with some of the sockets (apparent intermittent connection). This sometimes prevents appliances from working (intermittent power) and also appears to be causing issues with the ethernet powerline adapters we are using. I had an electrician take a look and he insisted there was only one faulty socket which he replaced and tested by plugging in some kind of tester. He didn't actually check ALL sockets in the flat. Anyway, the problem has persisted and I know we need to replace other sockets which I believe I can manage myself. However, I wanted to check if there are other issues.

    I acquired a Kewtech Loopcheck 107 plug-in socket tester. This has identified sockets with an intermittent fault when you wiggle the plugged in tester. But it also shows other things for all sockets:
    Loop test: amber (between 1.8 and 92 ohms)
    RCD check: depressing this button for a few seconds should trip the RCD. Nothing happens, but them I discovered on checking the consumer unit that there does not appear to be an RCD (see photo).

    Is this anything to be concerned about?
     

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  3. bernardgreen

    bernardgreen

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    Yes,

    The Loop test result should have a result of 1.8 Ohms or LOWER. 92 Ohms is dangerously high, especially as there is no RCD protecting the installation.

    That is something else to be concerned with, (1) that there is no RCD and (2) that you were not aware there was no RCD until you tried to test it.

    If he left you with the loop test reading greater than 1.8 Ohms then he is not a competent electrician.
     
  4. Taylortwocities

    Taylortwocities

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    There is no RCD in your consumer unit, so it cannot trip!

    To consider if the loop test at the sockets is too high, you first need to determine what the earth loop measurement is at the incoming point. You can’t do that with one if those plug in toys.

    I’m afraid you need an electrician on site ( not the same one) to sort this out. Of course, if your flat is rented then it’s the landlord’s responsibility.
     
  5. pachmarhi

    pachmarhi

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    thanks for confirming what I thought. I know the plug-in testers have limited value but figured it was a good starting point given that I have been stung by one bad electrician that came on recommendation! Used to have a good electrician I could draw on but alas no longer.
     
  6. flameport

    flameport

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    Multiple sockets suggests problems with the wiring. Very unlikely for multiple sockets to all be defective at the same time, just replacing the sockets is unlikely to fix anything.

    Unsafe, the maximum value for your socket circuits is 1.1 ohms.

    RCDs have been required for socket outlets since 1991. They are a requirement for almost all circuits now.

    Inner red / black insulation of the supply tails should not be visible outside of the consumer unit:
    ground-floor-CU.jpg

    Suggest you have someone inspect and test the whole installation, as there are multiple problems just from the limited information provided so far.
     
  7. pachmarhi

    pachmarhi

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    Thanks. Any suggestions on how to find a suitable electrician? My previous go to electrician is no longer available and going on local recommendation (via Nextdoor) and NICEIC accreditation doesn't seem to have helped much. The only reason I decided to investigate things further myself was because I didn't really trust the outcome of the previous electrician, given that I had actually asked him to do an inspection of the complete installation because I suspected other issues.
     
  8. Taylortwocities

    Taylortwocities

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    You could look here.
    https://www.electricalcompetentperson.co.uk/

    All listed are members of organisations like NAPIT, NICEIC, etc This means that they all have formal and practical skills and qualifications. Like every register, there’s no guarantee of ability, but a better place to look than My Builder, etc.

    better to use recommendations from friends and neighbours. Do let us know how you get on.
     
  9. ericmark

    ericmark

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    1.8 Ω is OK it is the lowest the Kewtech Loopcheck 107 can show, they are all the same, for a 20 amp MCB which is common for sockets in Europe you need 2.18 Ω to pass and with a radial with 25 amp the pass point is 1.75 Ω so unless used on a ring final 1.8 Ω is OK, the problem is in the rest of Europe they don't use ring finals so our 1.37 Ω is not required so they simply don't go down that low, and they are all the same. So as far as you can test with that plug in tester <1.8 Ω is a pass.

    Less than (<) 1.8 could be 1.37 Ω

    Over the <1.8 Ω is a failure with no RCD all TT supplies have had RCD protection from some where around the early 80's, TT means you have an earth rod, and you don't have earth rod, so the only reason to talk about it is that is why you have the other lights on the tester.

    In the days of the fuse, going a little high with the earth loop impedance (ELI) resulted in the fuse being a little slower to rupture, but in the days of the miniature circuit breaker it means you use the thermal part of trip instead of magnetic part so the tripping time is much longer.

    I would not use the socket showing a high ELI (over 1.8 Ω) but likely the others are OK. What you must remember is electricians don't use those plug in testers so likely don't realise 1.8 Ω is lowest reading.
     
    Last edited: 25 Jul 2020
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  11. winston1

    winston1

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  12. ericmark

    ericmark

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    I did feel when poster said stopped powerline adaptors working good. However the idea is to help, and just telling some one they have been sold some really poor devices does not help. as far as I am aware these RBCO's will fit they are no larger than the MCB they replace, [​IMG] however at £28.56 each that's £163 for all 6, (discount if more than 3 bought) and a new metal populated consumer unit (BG) from same firm is £62.10 and by changing to a cheaper make you can get RCBO's for as little as £10 each, so it needs some consideration as to route to go down.

    Personally I fitted CP electric RCBO's at £10 each as last house had two RCD's and I was fed up with random trips, and did not want that again, maybe not best move as fitted type AC, it said type B on the box, but was B curve not type B.

    It is how to move on which the poster needs to know, they already have found out power line adaptors are rubbish.
     
  13. Risteard

    Risteard

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    It should be noted that the site mentioned is invalid outside England and Wales.
     
  14. Taylortwocities

    Taylortwocities

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    It should be noted that the OP is located in London (not Londonderry). IIRC that is in England or Wales. Happy now?
    D710B659-5466-4A4F-92E0-A2BECA0987DB.jpeg
     
  15. winston1

    winston1

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    Londonderry is part of the UK as well.
     
  16. ericmark

    ericmark

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    But only just, a little north or west and your out, and last time I was there very few signs to tell you, if the signs direct to Derry you have wandered out.

    I do see the point people look at threads without asking questions, main place where I went to find tradesmen was the Pub, there is clearly a problem with that now.
     
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