Rules and Guidelines
Want to participate in the discussions? Please read our Community Rules and Guidelines. Need some help? Visit Support and Answers.

  • State Not Answered
  • Locked Locked
  • Replies 29 replies
  • Subscribers 32 subscribers
  • Views 2091 views
  • Users 0 members are here
Options
You may also be interested in
This discussion is locked.
You cannot post a reply to this discussion. If you have a question start a new discussion

Compliant?

Zoomup
Is this arrangement compliant or not?


Consumer unit. R.C.D. protected shower circuit supplied by a B40 M.C.B. which runs to a cord ceiling switch  in the shower room in 6.0mm2 T&E. Old electric shower removed. New power shower installed with water supplied from tanks. 0.63 Amp transformer in loft to feed new integral shower pump motor. Loft transformer fed via 3 Amp fused switched fused connection unit on a 1.0mm2 T&E cable from old shower ceiling cord switch. 1.0 mm2 T&E run 2.5 metres.


P.S. The switched fused connection unit is at the end of the supply cables.


Confirmation or condemnation by regs. please.


Z.
  • 0

    mapj1:

    The easy fix is to avoid questions about the length of cable before the 3A fuse, is to change  the 40A breaker for something smaller - for a 3A fuse, almost anything would do, 6A, 10A 16A - whatever is available .



    If "supplied from tanks" (my emphasis) in the OP means that the new shower unit does not heat the water, this is the obvious solution; but why not simply reposition the FCU?
  • 0
    Hello Chris,

                          the fused connection unit can not be re-positioned next to the shower cord switch as it is inaccessible above, and the customer does not want it in the shower room.  The fused connection unit is next to the shower transformer in the loft at the end of a 2.5m length of 1.0m2 T&E fed from the shower switch which is fused at 40 Amp. The consumer unit is inaccessible. to work on. You are correct, the new shower gets it water from tanks and does not contain a heating element. The transformer is only a 0.63 Amp load and is fused at 3 Amp so can not overload the 1.0mm2 T&E. Also a short is virtually impossible on the 1.0mm2 T&E as it is out of reach in the loft. The circuit is 30mA R.C.D. protected as well. The shower pump is E.L.V., but that is not my concern.


    Z.
  • 0
    The electric shower has been removed and the cord switch is inaccessible.  What has happened to the cable that used to supply the shower, is it still live, where is it in the wall and how has it been terminated?
  • 0

    (ii) "Be installed in such a manner as to reduce the risk of fault to a minimum." The cable is inaccessible as it runs under a tank stand and out of reach or risk of being stood on or mechanically damaged. 


    (iii) Just what requirement is meant here? Run in metal containment perhaps?



    The clause was traditionally used for things like fusebox tails and tap-offs from bus-bars. So something along the lines of insulated & sheathed singles (so there's double/reinforced insulation between live and c.p.c. (or other earthed parts) as well as between live conductors) run in such a way where basic insulation is exposed it can't touch other conductors, located where mechanical damage is unlikely and on a non-flammable surface would be the sort of arrangement I would have thought would comply. Live wires covered with only basic insulation shoved together into a back box behind the FCU and the cable itself run in the vicinity of timber joists (never mind all the other flammable detritus usually found in lofts) I still think falls short.


      - Andy.
  • 0

    Zoomup:

    The consumer unit is inaccessible.




    Need one say more? 132.12 and 513.1.


    In fact, it is obvious that you wouldn't have raised the question had you not had any uncertainty. From our acquaintance in here, I am sure that you will make the best of what seems to be a bad job.

  • 0

    AJJewsbury:




    (ii) "Be installed in such a manner as to reduce the risk of fault to a minimum." The cable is inaccessible as it runs under a tank stand and out of reach or risk of being stood on or mechanically damaged. 


    (iii) Just what requirement is meant here? Run in metal containment perhaps?



    The clause was traditionally used for things like fusebox tails and tap-offs from bus-bars. So something along the lines of insulated & sheathed singles (so there's double/reinforced insulation between live and c.p.c. (or other earthed parts) as well as between live conductors) run in such a way where basic insulation is exposed it can't touch other conductors, located where mechanical damage is unlikely and on a non-flammable surface would be the sort of arrangement I would have thought would comply. Live wires covered with only basic insulation shoved together into a back box behind the FCU and the cable itself run in the vicinity of timber joists (never mind all the other flammable detritus usually found in lofts) I still think falls short.


      - Andy.

     




    Thanks Andy,

                          the 1.0mm2 T&E is running on glass fibre flameproof insulation in a very clean and tidy environment with no rubbish or detritus near it at all. It does not run over any timber joists. I can not see any way that it can be damaged as it is under a tank stand and in an inaccessible area at the end of a loft. 


    Z.


     

  • 0

    Foffer:

    The electric shower has been removed and the cord switch is inaccessible.  What has happened to the cable that used to supply the shower, is it still live, where is it in the wall and how has it been terminated?


    The cord switch is still in situ attached to the upstairs shower room ceiling. It is still live and feeds the 1.0mm2 T&E that feeds just the new shower's 0.63 Amp E.L.V. transformer via. a fused connection unit with a 3 Amp fuse fitted in the loft by the loft hatch. 



    Z.




     

  • Former Community Member
    0 Former Community Member
    You're making a good case that it is safe - it is, however, clearly not "compliant"


    Regards


    OMS


  • 0
    The cord switch terminals would not be suitable for 1mm cable. 134.1.4
  • 0

    Foffer:

    The cord switch terminals would not be suitable for 1mm cable. 134.1.4


    That is why the 1.0mm2 copper was trippled over at the terminals. The connections are fine.


    Z.




     

Join us to get the best from IET EngX.

Joining EngX lets you personalise your experience so you stay up to date on the topics that interest you, plus you’ll be able to make connections who are looking to collaborate, exchange ideas and more.

Join us Not now

Community Rules & Guidelines