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Reg. 559.5.1.206 E.S. Lampholders.

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Why does the above regulation exempt E.S. lampholders if they comply with  BS EN 60238 from being connected in a specific way, i.e. with the outer connection being connected to the neutral of the supply please? Are they inherently safe?


Thanks in advance.


Z.


  • 0
    Assuming that N is at or close to earth potential, if you poke a finger in, the first bit that you will touch will not give you a shock and with further insertion, only your finger tip gets zapped.


    However, if the outer part were live, there would be a risk of hand to foot shock.
  • 0

    Chris Pearson:

    Assuming that N is at or close to earth potential, if you poke a finger in, the first bit that you will touch will not give you a shock and with further insertion, only your finger tip gets zapped.


    However, if the outer part were live, there would be a risk of hand to foot shock.




    Yes Chris I have always connected Live (phase) to the centre contact and Neutral to the outer terminal of E.S. lampholders in the past. But recently a customer asked me to install some new ceiling lights which had E14 E.S. insulated lampholders. The internal flex at the ceiling plate was just clear with no brown or blue indentification. That is why I am researching this matter. The above regulation seems to allow any combination of connection if the B.S. applies.


    Z.

  • 0
    The older style of E27 lamp holder had a metal screw shell into which the lamp screwed. This metal screw shell was readily touched since it was large and often only very slightly recessed into insulating material, also a lamp inserted halfway would have the exposed part of the screw base of the lamp exposed to touch whilst in contact with the outer contact of the holder. Regulations therefore required that the relatively safe neutral conductor was to be connected to the outer or screw shell connector and the much more dangerous line conductor connected to the well recessed center connection.


    Newer styles of e27 lamp holder have the threaded part of the holder made of insulating material. The connection to the threaded part of the lamp is made via a small spring contact at the base of this insulated threaded part. The two mains supply connections are therefore of broadly similar size and are recessed to a broadly similar degree.

    There is therefore no requirement for any particular polarity in making mains connections to this newer type of E27 lamp holder.


    I would still consider it to be better practice to connect the supply neutral to the outer contact, but that is my view of good practice and is not a regulatory requirement. My concern is that with a lamp inserted I don't like the threaded part of the lamp being dangerous to the touch as it is often more accessible than is desirable.
  • 0
    There was a product recall for some decorative lamps round Christmas. As part of the decoration, there was a metallic film round the glass globe, which became live on insertion, depending on how the ES lamp holder was connected. 


    Regards,


    Alan.
  • 0
    Foreign made lamps eh?


    Anyway, thanks all for your comments.


    Z.

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