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  1. Jay89
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    Jay89 Active EF Member

    Location:
    Herts
    Evening All

    Im sure this will have been discussed at some point (if so please point me to a relevant thread)

    I have been to look at some remedial work where a previous inspector has flagged up on multiple circuits 'DBx Cx has two cables in mcb, need separating - C2'

    These circuits are either lighting or radial power circuits supplying a small amount of sockets. All suitably rated and with decent R1+R2 readings.

    I have never seen this to be worthy of a mention let alone a C2 code, i have spoken to my CPS technical and they said they cant see an issue. Just looking for anyone else's opinion

    Thanks in advance!
     
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  2. buzzlightyear
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    buzzlightyear Electrician's Arms

    Location:
    star command
    have you got eicr test certs
     
  3. Jay89
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    Jay89 Active EF Member

    Location:
    Herts
    Not to hand but yes i have seen the full EICR
     
  4. telectrix
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    telectrix Scouser and Proud of It Trusted Advisor

    Location:
    cheshire/staffordshire
    Business Name:
    Telectrix
    so.you have 2 radials from 1 MCB and each is suitably protected by the In rating of the MCB and Zs readings are compliant. . what's the problem
     
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  5. buzzlightyear
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    buzzlightyear Electrician's Arms

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    star command
    did you take pic of c/u.
     
  6. Murdoch
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    Murdoch Electrician's Arms

    Location:
    Woking
    Sounds a load of bs to me.

    Need more information

    And you could have 10 cables in a mcb ..,
     
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  7. Jay89
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    Jay89 Active EF Member

    Location:
    Herts
    My thoughts exactly!
     
  8. buzzlightyear
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    buzzlightyear Electrician's Arms

    Location:
    star command
    if its feeding to2 radials and the appropriate mcb that should not be a problem.
     
    • Disagree Disagree x 1
  9. Jay89
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    Jay89 Active EF Member

    Location:
    Herts
    This is literally the extent of it, code 2 because as they put it two circuits supplied by one MCB.
     
  10. buzzlightyear
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    buzzlightyear Electrician's Arms

    Location:
    star command
    what a load of tosh.
     
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  11. Jay89
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    Jay89 Active EF Member

    Location:
    Herts
    Thanks, im glad you agree
     
  12. Midwest
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    Midwest Electrician's Arms

    Location:
    Oxfordshire
    Why aren't you soaking up the sun, and drinking those lite beers the Yanks favour, instead of wasting your time on here. Holiday of a life time you said!!
     
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  13. Midwest
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    Midwest Electrician's Arms

    Location:
    Oxfordshire
    Your EICR chaps, I don't know. What about RFC's, you got two cables in a mcb there :)
     
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  14. Jay89
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    Jay89 Active EF Member

    Location:
    Herts
    I think they're suggesting two radials rather than two cables is the issue, badly worded title. But yes the specific example they give in the OSG of taking a spur off RFC at the MCB came to mind when i saw it too.
     
  15. Des 56
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    Des 56 Trusted Advisor

    Location:
    Gliese 581C

    2 conductor mcb for rings and 1 conductor mcb for radials ?:)
     
    • Agree Agree x 1
  16. westward10
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    westward10 In echoed steps I walk across an empty dream. Electrician's Arms

    Location:
    Northamptonshire
    I would C3 it, two final circuits require individual circuit protection.
     
    • Disagree Disagree x 2
  17. davesparks
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    davesparks Trusted Advisor

    Location:
    guildford
    It's not two final circuits, it is one, the definition of a circuit in bs7671 is very clear on this.

    What basis do you have for a C3? What is the improvement that can be made? Unless this Mcb is overloaded, which is a separate matter, then nothing is improved by splitting it in to two circuits
     
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  18. Andy78
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    Andy78 Trusted Advisor

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    Kingston upon Hull
    I'm not biting :D
     
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  19. westward10
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    westward10 In echoed steps I walk across an empty dream. Electrician's Arms

    Location:
    Northamptonshire
    I suspect this is the case of an existing circuit and then someone lashing another to it because they cannot be be bothered to employ correct installation methods by using an additional protective device at a spare way or advising the existing board has inadequate capacity.
     
    • Disagree Disagree x 1
  20. Jay89
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    Jay89 Active EF Member

    Location:
    Herts
    There are multiple consumer units in this EICR where it has been flagged, from what i can see most seem to be part of original installation (same cable and paired dressing). Mostly on three phase boards with no spare ways.
     
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  21. davesparks
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    davesparks Trusted Advisor

    Location:
    guildford
    Based on what evidence? Whilst this is possibly what has happened, there is nothing in the regulations to prevent a circuit being extended in this way.
    If a radial socket circuit has the capacity for additional sockets, then why not extend it from the DB if that's the most logical place to connect it? Surely this is better than adding an additional joint into the circuit somewhere?
     
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  22. Jay89
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    Jay89 Active EF Member

    Location:
    Herts
    I should add it has detailed labelling at each consumer unit also
     
  23. westward10
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    westward10 In echoed steps I walk across an empty dream. Electrician's Arms

    Location:
    Northamptonshire
    See in day in day out and I will C3 it every time.
     
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  24. davesparks
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    davesparks Trusted Advisor

    Location:
    guildford
    And which regulation do you reference to support this observation?
     
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  25. buzzlightyear
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    buzzlightyear Electrician's Arms

    Location:
    star command
    was the boards marked up for the
    2 circuits to the mcb.
     
  26. westward10
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    westward10 In echoed steps I walk across an empty dream. Electrician's Arms

    Location:
    Northamptonshire
    314-01-04 off the top of my head but I suspect you know this.
     
    • Disagree Disagree x 1
  27. Jay89
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    Jay89 Active EF Member

    Location:
    Herts
    All points supplied by that MCB yes
     
  28. davesparks
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    davesparks Trusted Advisor

    Location:
    guildford
    I can't see anything in 314 to support your opinion, the closest thing is that each final circuit be connected to a separate way in a DB. There is nothing to say that a final circuit cannot comprise multiple branches from one ocpd.
     
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  29. buzzlightyear
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    buzzlightyear Electrician's Arms

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    star command
    reg 314.4
    when an installation comprise more then one final circuit .each final circuit shall be connected to a separate way in the distribution board .
     
  30. davesparks
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    davesparks Trusted Advisor

    Location:
    guildford
    Yes, now add the definition of a circuit.

    There is nothing which prevents a circuit being formed of two branches from an ocpd. This could be a better design if it reduces th overall length of the circuit
     
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  31. westward10
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    westward10 In echoed steps I walk across an empty dream. Electrician's Arms

    Location:
    Northamptonshire
    Old argument and my mind is not swayed, I agree with the Report the OP has but not the Coding.
     
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  32. davesparks
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    davesparks Trusted Advisor

    Location:
    guildford
    Yes an old argument, and one where you persistently ignore the bs7671 definition of a circuit, and have yet to provide the definition of a circuit which you work to.
     
  33. westward10
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    westward10 In echoed steps I walk across an empty dream. Electrician's Arms

    Location:
    Northamptonshire
    Yes yes yes heard all this and 314-01-04 refers to final circuit, I will not be swayed by sideway interpretations.
     
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  34. Andy78
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    Andy78 Trusted Advisor

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    You must be on a wind up quoting reg numbers from the 16th :laughing:
     
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  35. Murdoch
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    Murdoch Electrician's Arms

    Location:
    Woking
    Me thinks westward10 did the EICR.....
     
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  36. Murdoch
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    Murdoch Electrician's Arms

    Location:
    Woking
    Yup... Very true, but there's good wifi in the parks and there's time in the queues....

    It's 32 here now and we've just got back to the villa..... And I've just had a dip in the pool. It'll be beer o'clock very soon, not rubbish yank beer though....
     
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  37. davesparks
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    davesparks Trusted Advisor

    Location:
    guildford
    I don't think my interpretation is sideways, the definition of a circuit is clear, as is the regulation I think you are referring to, For the sake of avoiding ambiguity lets just call it the whole of 314.

    You still have not provided any clear definition of a circuit which you are referring to, nor any clear regulation which prohibits a circuit having two branches, or two legs, being fed from the middle of the circuit, etc.

    As it stands, if you were carrying out an eicr on an installation I had designed with a circuit of this nature then I think my lawyers would be ripping you a new one by now.
     
    • Agree Agree x 1
  38. westward10
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    westward10 In echoed steps I walk across an empty dream. Electrician's Arms

    Location:
    Northamptonshire
    Final circuit, and yes I will still C3 it lawyers or no lawyers.
     
    • Disagree Disagree x 1
  39. wirepuller
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    wirepuller Trusted Advisor

    Location:
    south uk
    Westward your argument has as much logic as the neutrals in switches argument. Some people just seem to stick their head in the sand and ignore facts.
    You seem to admit that it complies with 7671 and yet insist on coding it!
    You need to remember that coding can cost the occupier money, a lot of money. Unless you can justify a safety issue or a departure you CANT code.
    Coding because of your personal views is simply unacceptable.
     
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  40. telectrix
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    telectrix Scouser and Proud of It Trusted Advisor

    Location:
    cheshire/staffordshire
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    Telectrix
    fight ! handbags at dawn. :eek:
     
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  41. wirepuller
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    wirepuller Trusted Advisor

    Location:
    south uk
    Ooher!
    No handbags but I think Westwards needs to bear in mind that the type of code he is suggesting may result in a needless DB change just to gain ways.....
     
    • Agree Agree x 1
  42. westward10
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    westward10 In echoed steps I walk across an empty dream. Electrician's Arms

    Location:
    Northamptonshire
    Wrist slapped, I was quoting from the top of my head which is generally empty.
     
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  43. westward10
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    westward10 In echoed steps I walk across an empty dream. Electrician's Arms

    Location:
    Northamptonshire
    Don't recall suggesting it complied with BS7671 nor is it a personal view. I read Reg 314.4 that each final circuit should be given individual circuit protection that is it which I C3.
     
    • Disagree Disagree x 1
  44. wirepuller
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    wirepuller Trusted Advisor

    Location:
    south uk
    Ok. No point in going round in circles.
     
  45. charlie76
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    charlie76 Regular EF Member

    Location:
    Notts
    Business Name:
    CES Midlands
    I am of the same opinion as @davesparks@davesparks on this. It is one circuit no matter where the circuit is supplied from. If you have 2 radials in one MCB it is still one circuit with the supply to that circuit in the middle rather than at the end. If you consider the practicality of it, it actually is also safer. Consider you loose earth continuity on on leg of the circuit for whatever reason, the other leg of the circuit maintains its earth continuity. Also reduced loading if having 2 radials to the circuit means the overall length is reduced.

    My interpretation of 314 and specifically in this case 314.4 is that for example you had 2 circuits, say upstairs lighting and downstairs lighting, these should not be connected to one MCB.

    I would say it is down to the design and interpretation as to whether they should be separate circuits. If in the OP's case both radials in the MCB served a defined area (lets say downstairs) and the breaker is labelled so then I would personally say that is the downstairs lighting circuit. If one radial served the downstairs and the other radial served a light in the loft I would perhaps code it as C3 as there is a risk here of indirectly energising a final circuit intended to be isolated.

    On a tangent: Why does a BRITISH standard have an American spelling of energising?
     
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