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New EICR - "No earth bond to some socket boxes: C2"?

Former Community Member
Former Community Member
I have a new EICR which has the observation "No earth bond to some socket boxes: C2".


I have checked continuity between all faceplate mounting screws and the earth of the socket. They are all connected, i.e. the back box is at least earthed by the screw if not with a tail internally (I have not removed the front plates of any sockets). The earth of each socket is connected to the ring.


While it is best practice, is it a requirement of the regulations that a tail is connected internally?


many thanks



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  • 0
    Sparkingchip:

    >>>

    If you are doing testing for an EICR and you find a rewirable fuse board, a high PSC and 2.5 mm twin and earth with 1.0 mm all sorts of potential issues should be flagged up, because the earth conductor is only 0.15 mm bigger than the fuse wire.


    Andy Betteridge 


    Not quite as bad as that - the 0.85mm dia wire is not 0.85mm2 cross-section;  more like 3/4 of that (0.57mm2 to be exact) So the energy per unit length will be 57%, and the adiabatic  temperature rise (as not only is there less power, there is more volume of metal to heat ) will be 57% of 57%, or 0.32. So if the 0.85mm diameter fuse wire reaches 1100C and melts, the   CPC reaches something more like 340C and in that fraction of a second before it start to cool, it damages the surface of the PVC on either side of it. Not great, as the cable insulation will eventually fail,  but not likely to lead to the big danger of the CPC blowing open and the fuse remaining undamaged.

    Of course there is precious little margin if that 1mm cpc is nicked or strained at some point, and repeated firing of a fuse in rapid succession may blow the CPC clear eventually.


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  • 0
    Sparkingchip:

    >>>

    If you are doing testing for an EICR and you find a rewirable fuse board, a high PSC and 2.5 mm twin and earth with 1.0 mm all sorts of potential issues should be flagged up, because the earth conductor is only 0.15 mm bigger than the fuse wire.


    Andy Betteridge 


    Not quite as bad as that - the 0.85mm dia wire is not 0.85mm2 cross-section;  more like 3/4 of that (0.57mm2 to be exact) So the energy per unit length will be 57%, and the adiabatic  temperature rise (as not only is there less power, there is more volume of metal to heat ) will be 57% of 57%, or 0.32. So if the 0.85mm diameter fuse wire reaches 1100C and melts, the   CPC reaches something more like 340C and in that fraction of a second before it start to cool, it damages the surface of the PVC on either side of it. Not great, as the cable insulation will eventually fail,  but not likely to lead to the big danger of the CPC blowing open and the fuse remaining undamaged.

    Of course there is precious little margin if that 1mm cpc is nicked or strained at some point, and repeated firing of a fuse in rapid succession may blow the CPC clear eventually.


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