E14, E27 ES a question!

[CRiMiNaLNiNJa]

This has been bugging me, hope someone can clarify (preferably with evidence/source) what is so special about E14 & E27 light fixings and why they are excluded from other ES fixings with regards to centre pin polarity?

I'm assuming they are insulated in some form (Class II?).

I can't find anything on the internet or book (BS7671:2008, GN3, Lyndsy 2330 Lv2/3, Practical Guide to T&I et al)

Cheers in advance

 

[nickblake]

They are the size of the base of the lamp E is for eddison screw 27 is the size in mm E27 ,E14 is edison screw 14 mm hope that helps

 

[Sintra]

Reg 559.6.1.8 states that except for E14 & E27 lampholders complying with BS 60238 the outer contact should be connected to neutral.

BS 60238 refers to lampholders that are shrouded so direct contact is not possible with the lamp in the holder.

To make sure they comply with BS 60238 the metal ring and centre contact that connects with the threaded part of the lamp is set back deep inside the skirt and can't be touched unless you remove the lamp.
When the lamp is fitted it is not possible to touch any conductive part and when removing the lamp the contacts have to be broken before the threads are exposed.

E14 & E27 lampholders that are not BS 60238 therefore have to comply with 559.6.1.8

 

[CRiMiNaLNiNJa]

Thanks Sintra, that clears it up nicely for me, should have looked more into the BS 60238 methinks.

Cheers!