2 core cable Metal surround?

[Oikos100]

So I've just bought a plug-in wall-mounted light from Habitat (link at the end) which I intend to remove the cable from and wire into the mains.
Although I will use 3 core cable I was surprised to see that the existing cable used nis 2 core which goes into a plastic socket and the main surround is metal...
Is that allowed? I thought lights with metal shades (which effectively this is as it goes around the socket) had to use 3 core

It would be interesting to know as I hope to make some switched bedside lamps and thought I had to use 3 core if any of the components are metal.
Thanks

https://www.habitat.co.uk/wells-brass-wall-light-1788870

 

[Marvo]

It's possibly what's know as a ClassII item which means everything internal is double insulated which makes it a negligable chance it can become live and cause a shock if it's used as per manufacturers intentions and instructions. Rewiring it with a different cable and using it as anything but a walllight would not be a safe thing to do.

 

[James]

Looking at the spec,
It is a class 2 fitting, this requires no earth.

 

[telectrix]

in the description, (details and dimensions) it says it's class2. therefore it does not require earthing. it shouls somewhere have a symbol of a square within a square.

apart from that, though, it's hideous. looks like an american cop's bullhorn with an inflated condom on top.

 

[Oikos100]

Ha - thanks for your un-asked for opinion on the style! Actually part of the reason for rewiring it is that it is forming the basis for a bespoke designed light!

That aside - Would it be OK to buy a new earthed socket for the inside, 3 core cable and wire it into the mains? It's for my use, not to resell but I obviously want it to be safe.

 

[James]

Your plan will make you the manufacturer of an electrical appliance.

YOU ARE RESPONSIBLE for the design, construction, testing and documentation of the device.

There are too many unknowns to be advised via an Internet forum.

There are requirements to be met for class 2 appliances
Different requirements to be met for class 1 appliances.

Class 1 is the more onerous category and if you can’t be sure that you have met all the requirements of class 2 then I suggest that you design build and TEST the device to meet the class 1 requirements.

I am sure there is a British standard that details what the requirements are, however I am unsure of the number.

 

[Oikos100]

I will get this tested once made but I've thought of a better way to ask my question:

Same process as people who wire up wine bottles to make lamps only instead of a wine bottle I have a metal surround:

Basically 3 core cable is being wired into a metal earthed bulb holder.
The holder is then attached to this metal surround with a coupler to secure in position.

All standard off the shelf pieces.
The bespoke bit is a ceramic item which is being attached to the outside of the metal surround.

I guess people wire up pendants with metal shades this way
[automerge]1602021249[/automerge]
Links to the parts I'd like to use:

Earthed lamp holder

Coupler
and
Nipple
to secure lampholder to metal surround

Cable will then be inside the holder not outside as pictured

Is this correct?

Sorry for the long thread, any help is gratefully received as I need to get these ordered
Thanks

 

[Lucien Nunes]

Just because something is metal does not imply it needs earthing. It is recognised that when constructed to applicable standards, class II can be safer, as it does not become potentially dangerous if the earthing fails. Lamps are one of the items that can easily be made class II and manufacturers typically choose this option.

Your construction sounds about a simple as it can be but it still needs close scrutiny. E.g. what happens if the flex entry adaptor comes loose and the holder rotates relative to the flex entry, twisting the wires inside and potentially breaking them loose or chafing the cable against the bush? Can you do a realistic risk assessment on the relative merits of class I and class II in that situation and decide which gives the least risk? How are you going to calibrate the equipment you use for the cable pull-out test, or are you going to subcontract that to someone else? This is the type of searching question you need to ask and answer even with a simple product, not just 'does a metal surround need earthing.'

 

[Oikos100]

Hmmm, yes, thank you, I see your point! Perhaps we will have to make a 'feature' of the external cable.
Thank you for your help